Answer: Isotopes of an atom are different because they have different atomic masses and different number of neutrons within their nucleus. They are the same since they will always have the same atomic number/number of protons in their nucleus.
Explanation:
Air pollution exist in two forms namely ozone and particle pollution. CFCs and smog are under the ozone form of pollution. Ozone type of pollution is mostly formed by reaction between the sunlight and the vapors that are emitted due to human activities.
The mass of magnesium in 
atoms is 240 g.
Answer: Option A
<u>Explanation:</u>
First, we have to convert the atoms to moles of magnesium.
We know that atoms are present in 1 mole of magnesium. So,
Thus,
Thus, 240 g of Magnesium is present in atoms.
Answer:
water
Explanation:
The heat capacity of a material, along with its total mass and its temperature, tell us how much thermal energy is stored in a material. ... <u>The result is that the temperature of the water cube is much more stable than the air — the water changes much more slowly; it holds onto its temperature longer.</u>
4. Isotopes of the same element
