Answer:
B
Explanation:
B. There are two atoms of Nitrogen and two atoms of Hydrogen combined to make Ammonia.
The answer should be; 11
The atomic mass number is found by combining the number of protons and neutrons
Hope this helps :)
Explanation:
According to the law of conservation of mass, mass can neither be created nor destroyed but it can simply be transformed from one form to another.
For example, 
Mass of Na = 23 g/mol
Mass of Cl = 35.5 g/mol
Sum of mass of reactants = mass of Na + mass of Cl
= 23 + 35.5 g/mol
= 58.5 g/mol
Mass of product formed is as follows.
Mass of NaCl = mass of Na + mass of Cl
= (23 g/mol + 35.5) g/mol
= 58.5 g/mol
As mass reacted is equal to the amount of mass formed. This shows that mass is conserved.
As a result, law of conservation of mass is obeyed.
Partial pressure=mole fraction×Pt
x=0.044÷44(maolarmass of CO2)×Pt
x=0.044÷(44)2×Pt
x=5×10^-4×Pt
x=5×10^-4×Pt
where Pt:1atm=760mmHg
xatm=750mmHg
750×1÷760=0.99
now;5×10^-4×099=4.95×10^-4.
Pt=4.95×10^-4
Answer:
0.175mol
Explanation:
Mole of a substance can be calculated using the formula as follows:
number of moles (n) = mass (m) ÷ molar mass (MM)
According to this question, there are 4.2g of Magnesium (Mg).
Molar mass of Magnesium = 24g/mol, hence, the number of moles of 4.2g of Mg is as follows:
n = 4.2g ÷ 24g/mol
n = 0.175mol