In the Chemistry Formula Image question type, students can input complex chemistry formulas on an image, using response boxes.

Figure 1 - Chemistry Formula Image question example.


Create a Question

Enter the question stem into the Compose question area. You may want to use our Math Editor in order to insert a chemistry expression in the stimulus. For this click inside the Compose Question text area and select Math Editor from the Rich Text Editor panel (see Figure 2).

Figure 2 - Rich Text Editor panel with Math Editor button.

Then upload the image to be used for the question in the Add image field. You can either upload the image or paste image URL. For information about image requirements visit our Images page. Image alternative text appears if an image cannot be displayed on a page, and the Text on hoveris displayed when the cursor hovers over an image.

Figure 3 - Image Cloze Chemistry question basic parameters.

The uploaded image preview will be shown below in the Response Positions section.

You can then position the response boxes on the image. In order to add more response boxes click on +Add above the image. Response boxes will pop up on the image. Drag response boxes and position them on the image as required. See example in Figure 4.

Figure 4 - Positioning response containers on the image.

Each response container added on the image will have a number label. You can add multiple response boxes within one container and define specific dimensions for each container individually. For this you will need to configure the Edit individual response containers section. This can be found below the uploaded image. See below breakdown of attributes available:

  • Formula template - You can enter complex chemistry expressions and response boxes here. The Template is a LaTeX area. Chemistry expressions can be added with the LaTeX Keypad. You must enter {{response}} to indicate response boxes within a container. You can add multiple response boxes here.
  • Width and Height - You can enter container width and height in pixels, i.e. 60px and 30px, in order to change standard dimensions.

Follow these steps in order to configure validation:

  1. Insert a value in the Point(s) box to define a mark for the question. The default value is set to 1.
  2. In the Correct tab below you will see a Response submenu. There will be as many submenus as you have response containers on the image. Each submenu will be named Response 1, Response 2 , etc. depending on the number of response containers. Here you set validation separately for each container.
  3. Under each submenu select scoring method and enter the correct response in the Valuefield. In this example, we have two response containers and the student response should be the same as that in the validation area for both containers. In this case, set validation for Equation Value 1 and select equivLiteral as a scoring method, then enter the correct response in the Value field. See example in Figure 5.

Figure 5 - Validation settings for Image Cloze Chemistry question with two response containers.

4. Each scoring method has additional options that allows authors to set more precise validation conditions. A breakdown of all options associated with certain scoring methods can also be found in our Formula tutorials. When you select a scoring method all extra options will be displayed below the menu.

5. Some more complex chemistry questions will need a second scoring method applied. You can combine several scoring methods to set more strict validation rules. For instance, you may want the system to accept a response that is not only correct but is also given in certain measurement units. In this case, add another method called isUnit. Click the +Add button below the first scoring method to add a new scoring method.

More Options

Additional formatting options can be found under More Options:


Unscored/Practice usage - Removes all scoring from the question.

Penalty point(s) - The value entered here will be deducted from the student for an incorrect answer.

Minimum score if attempted - Set attempt marks for the question.

Check answer button - Show or hide the Check answer button from the student.

Check answer attempts - The value entered here refers to how many times the student can use the Check answer button, before it is disabled.


Transparent background - If this is enabled, the background of the response area will match the colour of the rest of the background area.

Response minimum width (px) - Enter, in pixels, the minimum width of the response area.

Template font scale - Scales the font relative to the question's font size. The default value is 150%.

Response container (global) and Edit invidiual response containers - Configure the Width and the Height, in pixels, for either all response containers, or for specified response containers.


Type - Select from a Floating keypad, a Block keypad, a Block on focus keypad, or no keypad.

Show keypad hints - Enable or disable hints on the keypad, such as keyboard shortcuts and symbol group titles that are shown on the top left corner of the keypad when hovering over a symbol group key.

Number pad - Customise the number pad in this section.

Symbols - Select what symbol groups will be shown to the student, or create custom symbol groups.

Text blocks

Use this option when you want to define a list of custom units (such as g, kg, cm, oz, etc.) that will not be rendered as LaTeX.

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