Answer is c , because it's convection currents
The mass of atoms of carbon and 3 molecules of hydrogen : 18 g/mol
<h3>Further explanation
</h3>
An atomic mass unit ( amu or "u") is a relative atomic mass of 1/12 the mass of an atom of carbon-12.
The molar mass(molecular mass-formula mass-molecular weight(MW)) of a compound is the sum of the relative atomic mass (Ar) of the constituent elements of the compound
Can be formulated :
M AxBy = (x.Ar A + y. Ar B)
The mass of atom of Carbon(C)⇒Ar = 12 g/mol
The mass of 1 molecule of Hydrogen - H₂(MW) : 2 g/mol
The mass of 3 molecules of Hydrogen : 3 x 2 = 6 g/mol
So the mass of atoms of carbon and 3 molecules of hydrogen :

Answer:a) 0.1 mole. b) 4g. c) 2% d) 196 mL
Explanation: in 200mL , 0.1mole
mw NaOH = 40g/mol —> 4g in 0.1 mole
4g in 200mL so 2g in 100mL
density NaOH = 1g/mL so if 4g in 200 mL, 4mL , 196 mL water
pH of buffer can be calculated as:
pH=pKa+log[salt]/[Acid]
As ka = 4.58 x 10-4
Concentration of [Salt] that is NO2(-1)=0.380M
Concentration of [Acid] that is HNO2=0.500M
So, pH= -log(4.58*10^-4)+log((0.380)/0.500))
=3.21
So pH of solution will be 3.21