Answer:
C
Explanation:
u can't touch a chemical with bare skin
A mole is mean the atomic number of 12 grams of carbon 12.
<span>it's a. carbon
</span>contain carbon<span>, </span>hydrogen<span>, oxygen, and nitrogen atoms. Certain amino acids also have sulfur atoms, phosphorus, or other trace elements such as iron or copper.</span>
Atmosphere is made of a mixture of gases. Each individual gas exerts a pressure known as the partial pressure.
The sum of the partial pressures exerted by each gas in the mixture is equal to the total pressure exerted by the mixture of gases as a whole.
The partial pressure depends on the composition of the gas in the mixture.
In this case the total pressure - 870 mmHg
21% of atmosphere is oxygen
partial pressure of Oxygen = 870 mmHg x 21% = 182.7 mmHg
Answer:
20 neutrons
Explanation:
neutrons = mass number - atomic number
mass number = 39, atomic number = 19
neutrons = 39 - 19 = 20
