Answer: Mass of zinc that reacts with 4.11 g of hydrochloric acid to form 9.1 g of zinc chloride and 3.97 g of hydrogen gas is 8.96 g
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Given: mass of hydrochloric acid = 4.11 g
Mass of products = Mass of zinc chloride + mass of hydrogen = 9.1 g + 3.97 g = 13.07 g
As mass of reactant = mass of products
mass of hydrochloric acid + mass of zinc = Mass of zinc chloride + mass of hydrogen
4.11 g + mass of zinc = 13.07 g
mass of zinc = 8.96 g
AgI has a higher melting point than vanillin because it is an ionic compound. The bonds are held more tightly together than in vanillin because it is a covalent compound. Ionic bonds have a higher melting point because the electrons are being transferred from one atom to the other.
Answer :
(1) The number of valence electrons present in the compound is, 20
(2) The number of bonded electrons present in the compound is, 16
(3) The number of lone pair electrons present in the compound is, 4
(4) The number of single bonds present in the compound is, 8
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that carbon has '4' valence electrons, hydrogen has '1' valence electrons and oxygen has '6' valence electrons.
Therefore, the total number of valence electrons in
= 2(4) + 6(1) + 6 = 20
According to Lewis-dot structure, there are 16 number of bonding electrons and 4 number of non-bonding electrons or lone pair of electrons.
The Lewis-dot structure of
is shown below.
25 g of NH₃ will produce 47.8 g of (NH₄)₂S
<u>Explanation:</u>
2 NH₃ + H₂S ----> (NH₄)₂S
Molecular weight of NH₃ = 17 g/mol
Molecular weight of (NH₄)₂S = 68 g/mol
According to the balanced reaction:
2 X 17 g of NH₃ produces 68 g of (NH₄)₂S
1 g of NH₃ will produce
g of (NH₄)₂S
25g of NH₃ will produce
of (NH₄)₂S
= 47.8 g of (NH₄)₂S
Therefore, 25 g of NH₃ will produce 47.8 g of (NH₄)₂S
Answer:
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mole
Explanation:
From the balanced
4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2
it is clear that 4 mol FeS₂ react with O₂ to give Fe₂O₃ and 8 mol of SO₂
First, we have to convert mass of SO₂ into No. of moles as following:
SO₂ has molar mass = 64 g/mol
No. of moles of SO₂ = (mass / molar mass) = (32 g / 64 g/mol) = 0.5 mol
we know that
4 mol FeS₂ gives→ 8 mol of SO₂
1 mol FeS₂ gives→ 2 mol of SO₂
??? mol FeS₂ gives→ 0.5 mol of SO₂
No. of moles of FeS₂ = (0.5 mol * 1 mol ) / 2 mol = 0.25 mol
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mol