Answer:
No
Explanation:
<em>No. </em>T<em>he demonstration does not violate the conservation of mass.</em>
<u>The law of conservation of mass states that mass can neither be created nor destroyed in a reaction. However, mass can be converted from one form to another during the reaction.</u>
In this case, even though the remaining bits of paper weigh 0.5 g while the original paper weighed 2.5 g, the ashes and smoke/gas from the burning will all add up to the lost weight of the paper.
<em>The burned part has been converted into other forms. If the smoke/gas and the ashes are properly captured, they will mark up with the weight of the remaining paper to give the weight of the original paper. </em>
Answer: 19kpa
Explanation:
The total pressure of a mixture of gases is the sum of the partial pressure exacted by the individual gases.
P total = P X + P Y
From the question above:
P total = P .nitrogen + P. oxygen
123.5kpa = 104.5kpa + P. Oxygen
P. Oxygen = 123.5kpa - 104.5kpa
= 19kpa
Answer:
b. I've seen a question like this before lol
The percentage yield is 72.8 %.
<em>Step 1</em>. Calculate the <em>mass of Br₂</em>
Mass of Br₂ = 20.0 mL Br₂ × (3.10 g Br₂/1 mL Br₂) = 62.00 g Br₂
<em>Step 2</em>. Calculate the <em>theoretical yield</em>
M_r: 159.81 266.69
2Al + 3Br₂ → 2AlBr₃
Moles of Br₂ = 62.00 g Br₂ × (1 mol Br₂/(159.81 g Br₂) = 0.3880 mol Br₂
Moles of AlBr₃ = 0.3880 mol Br₂ × (2 mol AlBr₃/(3 mol Br₂) = 0.2586 mol AlBr₃
Theor. yield of AlBr₃ = 0.2586 mol AlBr₃ × 266.99 g AlBr₃)/(1 mol AlBr₃)
= 69.05 g AlCl₃
<em>Step 3</em>. Calculate the <em>percentage yield
</em>
% yield = (actual yield/theoretical yield) × 100 % = (50.3 g/69.05 g) × 100 %
= 72.8 %