Answer:
Explanation:
The valance of magnesium atom is 
While the valence of nitrogen atom is 
Let us first write the first half-reactions
The second half reaction is
Adding the above two reactions and writing the final reaction, we get -
The balance equation is
Answer:
Mass of hydrogen produced = 2.1 g
Mass of excess reactant left = 25.2 g
Explanation:
Given data:
Mass of Mg = 50.0 g
Mass of HCl = 75.0 g
Mass of hydrogen produced = ?
Mass of excess reactant left = ?
Solution:
Chemical equation:
Mg + 2HCl → MgCl₂ + H₂
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 50 g/ 24 g/mol
Number of moles = 2.1 mol
Number of moles of HCl:
Number of moles = mass/molar mass
Number of moles = 75 g/ 36.5 g/mol
Number of moles = 2.1 mol
now we will compare the moles of hydrogen gas with both reactant.
Mg : H₂
1 : 1
2.1 : 2.1
HCl : H₂
2 : 1
2.1 : 1/2×2.1 = 1.05 mol
HCl is limiting reactant and will limit the yield of hydrogen gas.
Mass of hydrogen:
Mass = number of moles × molar mass
Mass= 1.05 mol ×2 g/mol
Mass = 2.1 g
Mg is present in excess.
Mass of Mg left:
HCl : Mg
2 : 1
2.1 : 1/2×2.1 = 1.05
Out of 2.1 moles of Mg 1.05 react with HCl.
Moles of Mg left = 2.1 mol - 1.05 mol = 1.05 mol
Mass of Mg left:
Mass = number of moles × molar mass
Mass = 1.05 mol × 24 g/mol
Mass = 25.2 g
NH3 is a gas at room temperature. Solutions of "ammonia" are made by bubbling NH3 through water, so there's no "pure ammonia" unless you are talking about the gas.
Explanation:
Mass = Density × Volume
where volume = 500ml and....
Density = 0.9901 g/ml
Mass = 0.9901 × 500
Mass = 495.05 g
The organic compound that is <span>used for stored chemical energy and contains carbon, hydrogen, oxygen, and often phosphorous is called lipid.
Lipids are molecules which consist of fats, waxes, and other things and their function is to store energy, and make up cell membranes.
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