Which change is chemical?(1 point)

Question

Responses

water freezing: liquid water becoming solid water

water boiling: solid water becoming gaseous water

water undergoing electrolysis: liquid water becoming oxygen and hydrogen molecules

water evaporating: liquid water becoming gaseous water

Answer 1

water undergoing electrolysis: liquid water becoming oxygen and hydrogen molecules

Answer 2

Which number remains unchanged during photosynthesis?(1 point)
Responses

the number of water molecules

the number of carbon atoms

the number of carbon dioxide molecules

the number of glucose molecules

Answer 3

the number of carbon atoms

Answer 4

In a chemical reaction, which aspect of the reactants changes?(1 point)
Responses

arrangement of the atoms

name of each element

nuclei

total mass

Answer 5

arrangement of the atoms

Answer 6

A young snake eats and digests a mouse. The increase in the snake’s mass equals(1 point)
Responses

only the mass of the mouse
only the mass of the mouse

the mass of the mouse plus the mass of waste produced by the snake.

the mass of the mouse plus the original mass of the snake.

the mass of the mouse minus the mass of waste produced by the snake.

Answer 7

the mass of the mouse plus the original mass of the snake.

Answer 8

Cellular respiration transforms glucose and oxygen into carbon dioxide, water, and energy.



C6H12O6 + 6O2 → 6CO2 + ?H2O + Energy



Based on the law of conservation of matter, what is the missing coefficient for water?

(1 point)
Responses

8

6

4

2

Answer 9

6