Speed=distance/time
D=150km
S=7200s
Divide the numbers.
150/7200=0.02km/s <---final answer
Molar mass Na = 23.0 g/mol
1 mol ---- 23.0 g
n mol ---- 69 g
n = 69 / 23.0
n = 3.0 moles
1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?
3.0 * 6.02x10²³ / 1
= 1.806x10²⁴ molecules
hope this helps!
Answer:
B. ethylamine.
Explanation:
- Since the compound contains NH₂, it is an amine compound.
- The alkyl group C₂H₅- contains 2 C atoms (ethyl group).
<em>So, the compound is ethylamine.</em>
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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!
