Answer: Option (C) is the correct answer.
Explanation:
When chemical composition of a substance is not changing in a chemical reaction then it is known as a physical change.
For example, when water change state, from ice to steam then it means solid state is changing into gaseous state.
Therefore, it is a physical change.
And, a reaction which causes change in chemical composition is known as a chemical change.
For example, 
Thus, we can conclude that we can see water change state, from ice to steam. This is a physical change in matter.
2NH₃(g) + CO₂(g) → CO(NH₂)₂(s) + H₂O(l)
is the balanced equation for the synthesis of urea.
Answer:
2: Moved faster and spread farther apart.
Explanation:
Restate the question: The movement of the liquid in a thermometer shows changes in temperature. An increase in temperature indicates the molecules in the liquid.
1. moved slower and closer together.
2.moved faster and spread farther apart.
3. contracted in size when heated.
4. expanded in size when heated.
Water that is cold does not have the energy to bounce of the walls, instead it is like a group of animals they group together for the warmth of the others when it gets really cold.
So it cant be 1.
We all know that power lines sag lower on a hot day (or a tire for a car, it has increases pressure). but those are different types of molecules.
So that rules out 3 and 4.
Which leaves you with 2.
The increase in temperature causes the water molecule to gain energy and move quickly, which resulted in water molecule that are farther apart and an increase in water volume.
Hope it helps!
Answer:
7 meters per second was her speed
Answer: Potassium perchlorate
Explanation: