Answer:
b. It exists in three different states at normal conditions in the Earth's atmosphere
Explanation:=
Snow, rain and water vapour can exist at normal conditions in the Earth's atmosphere.
a. is wrong. Only hydrogen and helium can escape Earth's atmosphere in significant amounts.
c. is wrong. The molecules of every substance are in motion even when it is solid.
d. is wrong. Other substances can form from a wide range of chemical processes.
e. is wrong. All substances expand when they become a gas.
Qual das alternativas a seguir é uma mistura homogênea?
Escolha uma:a. Mercúrio metálico e água. b. Gelo e água líquida. c. Areia e carvão em pó. d. Nitrogênio gasoso e vapor d’água. e. Poeira e ar atmosférico.
Answer:
<h3>The answer is 0.75 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula

From the question
mass = 90 g
volume = 120 mL
We have

We have the final answer as
<h3>0.75 g/mL</h3>
Hope this helps you