Oxygen and carbon dioxide
Answer:
The atomic mass of gallium (Ga) = <u>69.723 g/mol</u>
Explanation:
Given: Two isotopes of Gallium (Ga) are Gallium-69 (⁶⁹Ga) and Gallium-71 (⁷¹Ga)
<u>For ⁶⁹Ga: </u>
Relative abundance = 60.12% = 60.12 ÷ 100 = 0.6012; Atomic mass = 68.9257 g/mol
<u>For ⁷¹Ga:</u>
Relative abundance = 39.88% = 39.88 ÷ 100 = 0.3988; Atomic mass = 70.9249 g/mol
∴ The atomic mass of Ga = (Relative abundance of ⁶⁹Ga × Atomic mass of ⁶⁹Ga) + (Relative abundance of ⁷¹Ga × Atomic mass of ⁷¹Ga)
⇒ Atomic mass of Ga = (0.6012 × 68.9257 g/mol) + (0.3988 × 70.9249 g/mol) = <u>69.723 g/mol</u>
<u>Therefore, the atomic mass of gallium (Ga) = 69.723 g/mol</u>
Answer:
oxygen is an element because it is a pure substance which cannot be split into simpler substances by chemical means
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!
The force that accelerates objects towards Earth is gravity.
