diff --git a/js/AtomComponentEnum.js b/js/AtomComponentEnum.js
index f01952d..23a83c7 100644
--- a/js/AtomComponentEnum.js
+++ b/js/AtomComponentEnum.js
@@ -5,7 +5,7 @@
  *
  * @author Aadish
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   var AtomComponentEnum = {
diff --git a/js/AtomIdentifier.js b/js/AtomIdentifier.js
index 56ad698..0bcff67 100644
--- a/js/AtomIdentifier.js
+++ b/js/AtomIdentifier.js
@@ -8,10 +8,10 @@
  * @author Jesse Greenberg
  */
 
-define( function( require ) {
+define( require => {
   'use strict';
-  var shred = require( 'SHRED/shred' );
-  var Util = require( 'DOT/Util' );
+  const shred = require( 'SHRED/shred' );
+  const Util = require( 'DOT/Util' );
 
   // An arbitrary value used to signify a 'trace' abundance, meaning that a very small amount of this isotope is
   // present on Earth.
diff --git a/js/ShredConstants.js b/js/ShredConstants.js
index 67f549e..15bdd72 100644
--- a/js/ShredConstants.js
+++ b/js/ShredConstants.js
@@ -5,14 +5,14 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Bounds2 = require( 'DOT/Bounds2' );
-  var PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var shred = require( 'SHRED/shred' );
+  const Bounds2 = require( 'DOT/Bounds2' );
+  const PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const shred = require( 'SHRED/shred' );
 
   var ShredConstants = {
 
diff --git a/js/Utils.js b/js/Utils.js
index 0386294..d71f954 100644
--- a/js/Utils.js
+++ b/js/Utils.js
@@ -5,9 +5,9 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
-  var shred = require( 'SHRED/shred' );
+  const shred = require( 'SHRED/shred' );
 
   var Utils = {
     /**
diff --git a/js/model/NumberAtom.js b/js/model/NumberAtom.js
index a6843ea..d92aa4b 100644
--- a/js/model/NumberAtom.js
+++ b/js/model/NumberAtom.js
@@ -6,19 +6,19 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var DerivedProperty = require( 'AXON/DerivedProperty' );
-  var DerivedPropertyIO = require( 'AXON/DerivedPropertyIO' );
-  var Emitter = require( 'AXON/Emitter' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var NumberIO = require( 'TANDEM/types/NumberIO' );
-  var NumberProperty = require( 'AXON/NumberProperty' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const DerivedProperty = require( 'AXON/DerivedProperty' );
+  const DerivedPropertyIO = require( 'AXON/DerivedPropertyIO' );
+  const Emitter = require( 'AXON/Emitter' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const NumberIO = require( 'TANDEM/types/NumberIO' );
+  const NumberProperty = require( 'AXON/NumberProperty' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   // constants
   const NumberDerivedProperty = DerivedPropertyIO( NumberIO );
diff --git a/js/model/NumberAtomIO.js b/js/model/NumberAtomIO.js
index 60f026e..1d7be95 100644
--- a/js/model/NumberAtomIO.js
+++ b/js/model/NumberAtomIO.js
@@ -7,14 +7,14 @@
  * @author John Blanco (PhET Interactive Simulations)
  * @author Sam Reid (PhET Interactive Simulations)
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var ObjectIO = require( 'TANDEM/types/ObjectIO' );
-  var NumberAtom = require( 'SHRED/model/NumberAtom' );
-  var shred = require( 'SHRED/shred' );
-  var validate = require( 'AXON/validate' );
+  const ObjectIO = require( 'TANDEM/types/ObjectIO' );
+  const NumberAtom = require( 'SHRED/model/NumberAtom' );
+  const shred = require( 'SHRED/shred' );
+  const validate = require( 'AXON/validate' );
 
   class NumberAtomIO extends ObjectIO {
 
diff --git a/js/model/Particle.js b/js/model/Particle.js
index edde830..02be360 100644
--- a/js/model/Particle.js
+++ b/js/model/Particle.js
@@ -5,24 +5,24 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var BooleanProperty = require( 'AXON/BooleanProperty' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var NumberIO = require( 'TANDEM/types/NumberIO' );
-  var NumberProperty = require( 'AXON/NumberProperty' );
-  var ParticleIO = require( 'SHRED/model/ParticleIO' );
-  var PhetioObject = require( 'TANDEM/PhetioObject' );
-  var Property = require( 'AXON/Property' );
-  var PropertyIO = require( 'AXON/PropertyIO' );
-  var Range = require( 'DOT/Range' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Vector2 = require( 'DOT/Vector2' );
-  var Vector2Property = require( 'DOT/Vector2Property' );
+  const BooleanProperty = require( 'AXON/BooleanProperty' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const NumberIO = require( 'TANDEM/types/NumberIO' );
+  const NumberProperty = require( 'AXON/NumberProperty' );
+  const ParticleIO = require( 'SHRED/model/ParticleIO' );
+  const PhetioObject = require( 'TANDEM/PhetioObject' );
+  const Property = require( 'AXON/Property' );
+  const PropertyIO = require( 'AXON/PropertyIO' );
+  const Range = require( 'DOT/Range' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Vector2 = require( 'DOT/Vector2' );
+  const Vector2Property = require( 'DOT/Vector2Property' );
 
   // constants
   var DEFAULT_PARTICLE_VELOCITY = 200; // Basically in pixels/sec.
diff --git a/js/model/ParticleAtom.js b/js/model/ParticleAtom.js
index 83ff2e5..4cba7ad 100644
--- a/js/model/ParticleAtom.js
+++ b/js/model/ParticleAtom.js
@@ -6,27 +6,27 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var DerivedProperty = require( 'AXON/DerivedProperty' );
-  var DerivedPropertyIO = require( 'AXON/DerivedPropertyIO' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var LinearFunction = require( 'DOT/LinearFunction' );
-  var NumberIO = require( 'TANDEM/types/NumberIO' );
-  var ObservableArray = require( 'AXON/ObservableArray' );
-  var ObservableArrayIO = require( 'AXON/ObservableArrayIO' );
-  var ParticleAtomIO = require( 'SHRED/model/ParticleAtomIO' );
-  var ParticleIO = require( 'SHRED/model/ParticleIO' );
-  var PhetioObject = require( 'TANDEM/PhetioObject' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Utils = require( 'SHRED/Utils' );
-  var Vector2 = require( 'DOT/Vector2' );
-  var Vector2Property = require( 'DOT/Vector2Property' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const DerivedProperty = require( 'AXON/DerivedProperty' );
+  const DerivedPropertyIO = require( 'AXON/DerivedPropertyIO' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const LinearFunction = require( 'DOT/LinearFunction' );
+  const NumberIO = require( 'TANDEM/types/NumberIO' );
+  const ObservableArray = require( 'AXON/ObservableArray' );
+  const ObservableArrayIO = require( 'AXON/ObservableArrayIO' );
+  const ParticleAtomIO = require( 'SHRED/model/ParticleAtomIO' );
+  const ParticleIO = require( 'SHRED/model/ParticleIO' );
+  const PhetioObject = require( 'TANDEM/PhetioObject' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Utils = require( 'SHRED/Utils' );
+  const Vector2 = require( 'DOT/Vector2' );
+  const Vector2Property = require( 'DOT/Vector2Property' );
 
   // constants
   var NUM_ELECTRON_POSITIONS = 10; // first two electron shells, i.e. 2 + 8
diff --git a/js/model/ParticleAtomIO.js b/js/model/ParticleAtomIO.js
index 3fff951..6028590 100644
--- a/js/model/ParticleAtomIO.js
+++ b/js/model/ParticleAtomIO.js
@@ -6,16 +6,16 @@
  * @author John Blanco (PhET Interactive Simulations)
  * @author Sam Reid (PhET Interactive Simulations)
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var ObjectIO = require( 'TANDEM/types/ObjectIO' );
-  var shred = require( 'SHRED/shred' );
-  var validate = require( 'AXON/validate' );
+  const ObjectIO = require( 'TANDEM/types/ObjectIO' );
+  const shred = require( 'SHRED/shred' );
+  const validate = require( 'AXON/validate' );
 
   // ifphetio
-  var phetioEngine = require( 'ifphetio!PHET_IO/phetioEngine' );
+  const phetioEngine = require( 'ifphetio!PHET_IO/phetioEngine' );
 
   class ParticleAtomIO extends ObjectIO {
 
diff --git a/js/model/ParticleIO.js b/js/model/ParticleIO.js
index eccecce..30960fa 100644
--- a/js/model/ParticleIO.js
+++ b/js/model/ParticleIO.js
@@ -6,12 +6,12 @@
  * @author Sam Reid (PhET Interactive Simulations)
  * @author Andrew Adare (PhET Interactive Simulations)
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var ObjectIO = require( 'TANDEM/types/ObjectIO' );
-  var shred = require( 'SHRED/shred' );
+  const ObjectIO = require( 'TANDEM/types/ObjectIO' );
+  const shred = require( 'SHRED/shred' );
 
   class ParticleIO extends ObjectIO {
 
diff --git a/js/shred.js b/js/shred.js
index 6249f31..7350956 100644
--- a/js/shred.js
+++ b/js/shred.js
@@ -5,11 +5,11 @@
  *
  * @author Aadish Gupta
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Namespace = require( 'PHET_CORE/Namespace' );
+  const Namespace = require( 'PHET_CORE/Namespace' );
 
   return new Namespace( 'shred' );
 } );
\ No newline at end of file
diff --git a/js/view/AtomNode.js b/js/view/AtomNode.js
index a7156e5..0dcf51e 100644
--- a/js/view/AtomNode.js
+++ b/js/view/AtomNode.js
@@ -6,31 +6,31 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var ElectronCloudView = require( 'SHRED/view/ElectronCloudView' );
-  var ElectronShellView = require( 'SHRED/view/ElectronShellView' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var Path = require( 'SCENERY/nodes/Path' );
-  var PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var Property = require( 'AXON/Property' );
-  var Shape = require( 'KITE/Shape' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Text = require( 'SCENERY/nodes/Text' );
-  var Vector2 = require( 'DOT/Vector2' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const ElectronCloudView = require( 'SHRED/view/ElectronCloudView' );
+  const ElectronShellView = require( 'SHRED/view/ElectronShellView' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const Path = require( 'SCENERY/nodes/Path' );
+  const PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const Property = require( 'AXON/Property' );
+  const Shape = require( 'KITE/Shape' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Text = require( 'SCENERY/nodes/Text' );
+  const Vector2 = require( 'DOT/Vector2' );
 
   // strings
-  var minusSignIonString = require( 'string!SHRED/minusSignIon' );
-  var neutralAtomString = require( 'string!SHRED/neutralAtom' );
-  var positiveSignIonString = require( 'string!SHRED/positiveSignIon' );
-  var stableString = require( 'string!SHRED/stable' );
-  var unstableString = require( 'string!SHRED/unstable' );
+  const minusSignIonString = require( 'string!SHRED/minusSignIon' );
+  const neutralAtomString = require( 'string!SHRED/neutralAtom' );
+  const positiveSignIonString = require( 'string!SHRED/positiveSignIon' );
+  const stableString = require( 'string!SHRED/stable' );
+  const unstableString = require( 'string!SHRED/unstable' );
 
   // constants
   var ELEMENT_NAME_FONT_SIZE = 22;
diff --git a/js/view/BucketDragHandler.js b/js/view/BucketDragHandler.js
index 2007408..fba7004 100644
--- a/js/view/BucketDragHandler.js
+++ b/js/view/BucketDragHandler.js
@@ -7,14 +7,14 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var inherit = require( 'PHET_CORE/inherit' );
-  var shred = require( 'SHRED/shred' );
-  var SimpleDragHandler = require( 'SCENERY/input/SimpleDragHandler' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const shred = require( 'SHRED/shred' );
+  const SimpleDragHandler = require( 'SCENERY/input/SimpleDragHandler' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   /**
    * @param {Bucket} bucket
diff --git a/js/view/ElectronCloudView.js b/js/view/ElectronCloudView.js
index 949e79e..cfe8d52 100644
--- a/js/view/ElectronCloudView.js
+++ b/js/view/ElectronCloudView.js
@@ -6,17 +6,17 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Circle = require( 'SCENERY/nodes/Circle' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var RadialGradient = require( 'SCENERY/util/RadialGradient' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var SimpleDragHandler = require( 'SCENERY/input/SimpleDragHandler' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const Circle = require( 'SCENERY/nodes/Circle' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const RadialGradient = require( 'SCENERY/util/RadialGradient' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const SimpleDragHandler = require( 'SCENERY/input/SimpleDragHandler' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   /**
    * @param {ParticleAtom} atom
diff --git a/js/view/ElectronShellView.js b/js/view/ElectronShellView.js
index 8ddff89..2267158 100644
--- a/js/view/ElectronShellView.js
+++ b/js/view/ElectronShellView.js
@@ -6,17 +6,17 @@
  * @author John Blanco
  */
 
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Circle = require( 'SCENERY/nodes/Circle' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var KeyboardUtil = require( 'SCENERY/accessibility/KeyboardUtil' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var Property = require( 'AXON/Property' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const Circle = require( 'SCENERY/nodes/Circle' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const KeyboardUtil = require( 'SCENERY/accessibility/KeyboardUtil' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const Property = require( 'AXON/Property' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   // constants
   var LINE_DASH = [ 4, 5 ];
diff --git a/js/view/ExpandedPeriodicTableNode.js b/js/view/ExpandedPeriodicTableNode.js
index 0801062..759b4ad 100644
--- a/js/view/ExpandedPeriodicTableNode.js
+++ b/js/view/ExpandedPeriodicTableNode.js
@@ -4,22 +4,22 @@
  *
  * @author Aadish Gupta (PhET Interactive Simulations)
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Line = require( 'SCENERY/nodes/Line' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var PeriodicTableNode = require( 'SHRED/view/PeriodicTableNode' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Text = require( 'SCENERY/nodes/Text' );
-  var TextPushButton = require( 'SUN/buttons/TextPushButton' );
-  var Vector2 = require( 'DOT/Vector2' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Line = require( 'SCENERY/nodes/Line' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const PeriodicTableNode = require( 'SHRED/view/PeriodicTableNode' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Text = require( 'SCENERY/nodes/Text' );
+  const TextPushButton = require( 'SUN/buttons/TextPushButton' );
+  const Vector2 = require( 'DOT/Vector2' );
 
   // constants
   // 2D array that defines the table structure.
@@ -34,7 +34,7 @@ define( function( require ) {
   var BUTTON_SIZE = 50;
 
   // strings
-  var periodicTableString = require( 'string!SHRED/periodicTable' );
+  const periodicTableString = require( 'string!SHRED/periodicTable' );
 
   /**
    * @param {NumberAtom} numberAtom
diff --git a/js/view/InteractiveSchematicAtom.js b/js/view/InteractiveSchematicAtom.js
index 71c98fb..dc57ecf 100644
--- a/js/view/InteractiveSchematicAtom.js
+++ b/js/view/InteractiveSchematicAtom.js
@@ -3,19 +3,19 @@
 /**
  * Node that depicts an interactive atom where the user can add subatomic particles from a set of buckets.
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var AtomNode = require( 'SHRED/view/AtomNode' );
-  var BucketDragHandler = require( 'SHRED/view/BucketDragHandler' );
-  var BucketFront = require( 'SCENERY_PHET/bucket/BucketFront' );
-  var BucketHole = require( 'SCENERY_PHET/bucket/BucketHole' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var ParticleView = require( 'SHRED/view/ParticleView' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const AtomNode = require( 'SHRED/view/AtomNode' );
+  const BucketDragHandler = require( 'SHRED/view/BucketDragHandler' );
+  const BucketFront = require( 'SCENERY_PHET/bucket/BucketFront' );
+  const BucketHole = require( 'SCENERY_PHET/bucket/BucketHole' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const ParticleView = require( 'SHRED/view/ParticleView' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   // constants
   var NUM_NUCLEON_LAYERS = 5; // This is based on max number of particles, may need adjustment if that changes.
diff --git a/js/view/IsotopeCanvasNode.js b/js/view/IsotopeCanvasNode.js
index f571006..5039ceb 100644
--- a/js/view/IsotopeCanvasNode.js
+++ b/js/view/IsotopeCanvasNode.js
@@ -5,13 +5,13 @@
  *
  * @author Aadish Gupta
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var CanvasNode = require( 'SCENERY/nodes/CanvasNode' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var shred = require( 'SHRED/shred' );
+  const CanvasNode = require( 'SCENERY/nodes/CanvasNode' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const shred = require( 'SHRED/shred' );
 
   /**
    * A particle layer rendered on canvas
diff --git a/js/view/IsotopeElectronCloudView.js b/js/view/IsotopeElectronCloudView.js
index 48d15fd..1d2a941 100644
--- a/js/view/IsotopeElectronCloudView.js
+++ b/js/view/IsotopeElectronCloudView.js
@@ -11,16 +11,16 @@
  * @author Jesse Greenberg
  * @author Aadish Gupta
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Circle = require( 'SCENERY/nodes/Circle' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var LinearFunction = require( 'DOT/LinearFunction' );
-  var RadialGradient = require( 'SCENERY/util/RadialGradient' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const Circle = require( 'SCENERY/nodes/Circle' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const LinearFunction = require( 'DOT/LinearFunction' );
+  const RadialGradient = require( 'SCENERY/util/RadialGradient' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   // constants
   var MAX_ELECTRONS = 10; // For neon.
diff --git a/js/view/IsotopeNode.js b/js/view/IsotopeNode.js
index 134cba3..9b46b0e 100644
--- a/js/view/IsotopeNode.js
+++ b/js/view/IsotopeNode.js
@@ -4,17 +4,17 @@
  * Particle, represented as a circle with a gradient.  This type does not
  * track a particle, use ParticleView for that.
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var Circle = require( 'SCENERY/nodes/Circle' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var RadialGradient = require( 'SCENERY/util/RadialGradient' );
-  var RichText = require( 'SCENERY/nodes/RichText' );
-  var shred = require( 'SHRED/shred' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const Circle = require( 'SCENERY/nodes/Circle' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const RadialGradient = require( 'SCENERY/util/RadialGradient' );
+  const RichText = require( 'SCENERY/nodes/RichText' );
+  const shred = require( 'SHRED/shred' );
 
   /**
    * @param {Particle} isotope
diff --git a/js/view/ParticleCountDisplay.js b/js/view/ParticleCountDisplay.js
index 11ab1b3..7769e3f 100644
--- a/js/view/ParticleCountDisplay.js
+++ b/js/view/ParticleCountDisplay.js
@@ -7,25 +7,25 @@
  * @author John Blanco
  * @author Aadish Gupta
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var Panel = require( 'SUN/Panel' );
-  var ParticleNode = require( 'SHRED/view/ParticleNode' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var Rectangle = require( 'SCENERY/nodes/Rectangle' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Text = require( 'SCENERY/nodes/Text' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const Panel = require( 'SUN/Panel' );
+  const ParticleNode = require( 'SHRED/view/ParticleNode' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const Rectangle = require( 'SCENERY/nodes/Rectangle' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Text = require( 'SCENERY/nodes/Text' );
 
   // strings
-  var electronsColonString = require( 'string!SHRED/electronsColon' );
-  var neutronsColonString = require( 'string!SHRED/neutronsColon' );
-  var protonsColonString = require( 'string!SHRED/protonsColon' );
+  const electronsColonString = require( 'string!SHRED/electronsColon' );
+  const neutronsColonString = require( 'string!SHRED/neutronsColon' );
+  const protonsColonString = require( 'string!SHRED/protonsColon' );
 
   // constants
   var TITLE_MAX_WIDTH_PROPORTION = 1 / 3;
diff --git a/js/view/ParticleNode.js b/js/view/ParticleNode.js
index 31e3b85..bc67aa5 100644
--- a/js/view/ParticleNode.js
+++ b/js/view/ParticleNode.js
@@ -4,16 +4,16 @@
  * Particle, represented as a circle with a gradient.  This type does not
  * track a particle, use ParticleView for that.
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
-  var Circle = require( 'SCENERY/nodes/Circle' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
-  var RadialGradient = require( 'SCENERY/util/RadialGradient' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const Circle = require( 'SCENERY/nodes/Circle' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
+  const RadialGradient = require( 'SCENERY/util/RadialGradient' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   /**
    * @param {string} particleType - proton, neutron, or electron
diff --git a/js/view/ParticleView.js b/js/view/ParticleView.js
index df71fa7..ccf72eb 100644
--- a/js/view/ParticleView.js
+++ b/js/view/ParticleView.js
@@ -3,18 +3,18 @@
 /**
  * Type that represents a sub-atomic particle in the view.
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var Bounds2 = require( 'DOT/Bounds2' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var IsotopeNode = require( 'SHRED/view/IsotopeNode' );
-  var MovableDragHandler = require( 'SCENERY_PHET/input/MovableDragHandler' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var ParticleNode = require( 'SHRED/view/ParticleNode' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
+  const Bounds2 = require( 'DOT/Bounds2' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const IsotopeNode = require( 'SHRED/view/IsotopeNode' );
+  const MovableDragHandler = require( 'SCENERY_PHET/input/MovableDragHandler' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const ParticleNode = require( 'SHRED/view/ParticleNode' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
 
   // helper factory function
   function createParticleNode( particle, modelViewTransform, tandem ) {
diff --git a/js/view/PeriodicTableCell.js b/js/view/PeriodicTableCell.js
index f9a73c5..b0debfc 100644
--- a/js/view/PeriodicTableCell.js
+++ b/js/view/PeriodicTableCell.js
@@ -5,20 +5,20 @@
  * @author John Blanco
  * @author Aadish Gupta
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
   const EventType = require( 'TANDEM/EventType' );
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var FireListener = require( 'SCENERY/listeners/FireListener' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
-  var PhetFont = require( 'SCENERY_PHET/PhetFont' );
-  var Rectangle = require( 'SCENERY/nodes/Rectangle' );
-  var shred = require( 'SHRED/shred' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Text = require( 'SCENERY/nodes/Text' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const FireListener = require( 'SCENERY/listeners/FireListener' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const PhetColorScheme = require( 'SCENERY_PHET/PhetColorScheme' );
+  const PhetFont = require( 'SCENERY_PHET/PhetFont' );
+  const Rectangle = require( 'SCENERY/nodes/Rectangle' );
+  const shred = require( 'SHRED/shred' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Text = require( 'SCENERY/nodes/Text' );
 
   // constants
   var NOMINAL_CELL_DIMENSION = 25;
diff --git a/js/view/PeriodicTableNode.js b/js/view/PeriodicTableNode.js
index c818760..603a5d0 100644
--- a/js/view/PeriodicTableNode.js
+++ b/js/view/PeriodicTableNode.js
@@ -3,17 +3,17 @@
 /**
  * Scenery node that defines a periodic table of the elements.
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
-  var AtomIdentifier = require( 'SHRED/AtomIdentifier' );
-  var inherit = require( 'PHET_CORE/inherit' );
-  var Node = require( 'SCENERY/nodes/Node' );
-  var PeriodicTableCell = require( 'SHRED/view/PeriodicTableCell' );
-  var shred = require( 'SHRED/shred' );
-  var ShredConstants = require( 'SHRED/ShredConstants' );
-  var Tandem = require( 'TANDEM/Tandem' );
-  var Vector2 = require( 'DOT/Vector2' );
+  const AtomIdentifier = require( 'SHRED/AtomIdentifier' );
+  const inherit = require( 'PHET_CORE/inherit' );
+  const Node = require( 'SCENERY/nodes/Node' );
+  const PeriodicTableCell = require( 'SHRED/view/PeriodicTableCell' );
+  const shred = require( 'SHRED/shred' );
+  const ShredConstants = require( 'SHRED/ShredConstants' );
+  const Tandem = require( 'TANDEM/Tandem' );
+  const Vector2 = require( 'DOT/Vector2' );
 
   // constants
   // 2D array that defines the table structure.