<span>(4) The dissolving of the LiBr(s) in water is an exothermic process</span>
Answer:
561 g P₂O₃
Explanation:
To find the mass of P₂O₃, you need to (1) convert moles H₃PO₃ to moles P₂O₃ (via mole-to-mole ratio from equation coefficients) and then (2) convert moles P₂O₃ to grams P₂O₃ (via molar mass). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the amount of sig figs in the given value.
Atomic Mass (P): 30.974 g/mol
Atomic Mass (O): 15.998 g/mol
Molar Mass (P₂O₃): 2(30.974 g/mol) + 3(15.998 g/mol)
Molar Mass (P₂O₃): 109.942 g/mol
1 P₂O₃ + 3 H₂O -----> 2 H₃PO₃
10.2 moles H₃PO₃ 1 mole P₂O₃ 109.942 g
---------------------------- x -------------------------- x ------------------- = 561 g P₂O₃
2 moles H₃PO₃ 1 mole
Combustion involves with heat. The answer is burning wood.
Answer:Trials are repetitions of the same procedure. These are done for a couple of reasons: To minimize the impacts of errors done in any one trial by averaging multiple trials together. To minimize random effects and the effects of uncontrolled variables by averaging multiple trials together.
Explanation:
<span>1) Use the balanced chemical equation to find the molar ratios (proportions) of each product and reactant.
3N2H4(l)→4NH3(g)+N2(g)
=> molar ratios: 3 mol N2H4 : 4 mol NH3
2) Use the product to reactant molar ratio, and the quantity of reactant to determine the yield:
2.0 mol N2H4 * [4mol NH3] / [3mol N2H4] = 2*4/3 mol NH3 = 2.7 mol NH3
Answer: 2.7 mol
</span>
