I believe D hopefully this helps
Expansion
Explanation:
Expansion is the change is size of a body with increasing temperature and tension.
Bridges are built of iron. Iron thermally expands in the presence of increased temperature during the day. The length of the iron will increase by simple fractions. At night, when temperature drops, the bar returns back to its initial position.
- The allowance for expansion of the metal is made in order to prevent tension within the structure.
- Not doing this will cause the material to break since there is no free space for the bar to change shape.
Learn more:
Expansion in gases brainly.com/question/9979757
#learnwithBrainly
Oxygen gas produced : 0.7 g
<h3>Further explanation</h3>
Given
10.0 grams HgO
9.3 grams Hg
Required
Oxygen gas produced
Solution
Reaction⇒Decomposition
2HgO(s)⇒2Hg(l)+O₂(g)
Conservation of mass applies to a closed system, where the masses before and after the reaction are the same
mass of reactants = mass of products
mass HgO = mass Hg + mass O₂
10 g = 9.3 g + mass O₂
mass O₂ = 0.7 g
the time required for the activity of a substance taken into the body to lose one half its initial effectiveness. Informal. a brief period during which something flourishes before dying out.
hope this helps ^^
Molecules move from areas of high concentration to areas of low concentration.