Practice Pakistan questions with answers and explanations.
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The y-component is A sinθ.
10 sin30° = 10×0.5 = 5.
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Molarity equals moles divided by liters of solution.
0.50/2.0 = 0.25 M.
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Vectors in the same direction add directly.
The resultant is 12+7 = 19 N.
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Stoichiometry uses balanced equations to relate amounts.
It supports mass, mole, particle, and gas calculations.
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Moles equal mass divided by molar mass.
18 g ÷ 18 g/mol = 1 mol.
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Mass equals moles multiplied by molar mass.
2×58.5 = 117 g.
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Particles equal moles times Avogadro's number.
0.5×6.022×10^23 = 3.011×10^23 molecules.
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Moles equal particles divided by Avogadro's number.
1.2044×10^24 ÷ 6.022×10^23 = 2 mol.
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Carbon contributes about 12 and two oxygens contribute 32.
The total molar mass is about 44 g/mol.
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Oxygen contributes 16 of the 18 g/mol formula mass.
16/18×100 ≈ 88.9%.
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The coefficients of H2 and H2O are equal.
Thus 4 mol H2 produce 4 mol H2O.
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The mole ratio H2:NH3 is 3:2.
6 mol H2×2/3 = 4 mol NH3.
