Answer:
83.9g of sulfuric acid is the minimum mass you would need
1.73g of hydrogen would be produced
Explanation:
Based on the reaction:
2 Al(s) + 3 H₂SO₄(aq) → Al₂(SO₄)₃(aq) + 3 H₂(g)
2 moles of solid aluminium react with 3 moles of sulfuric acid. Also, two moles of Al produce 3 moles of hydrogen gas.
15.4g of Al are:
15.4g Al × (1mol / 26.98g) = 0.571 moles of Al.
Moles of sulfuric acid:
0.571 moles Al × (3 mol H₂SO₄ / 2 mol Al) = 0.8565 moles H₂SO₄
In grams:
0.8565 moles H₂SO₄ × (98g / 1mol) = <em>83.9g of sulfuric acid is the minimum mass you would need</em>
In the same way, moles of hydrogen produced are:
0.571 moles Al × (3 mol H₂ / 2 mol Al) = 0.8565 moles H₂
In grams:
0.8565 moles H₂ × (2.015g / 1mol) = <em>1.73g of hydrogen would be produced</em>
Answer:
The heat capacity for the sample is 0.913 J/°C
Explanation:
This is the formula for heat capacity that help us to solve this:
Q / (Final T° - Initial T°) = c . m
where m is mass and c, the specific heat of the substance
27.4 J / (80°C - 50°C) = c . 6.2 g
[27.4 J / (80°C - 50°C)] / 6.2 g = c
27.4 J / 30°C . 1/6.2g = c
0.147 J/g°C = c
Therefore, the heat capacity is 0.913 J/°C
Answer: 6.02 x 10^25
Explanation:
In order to find the number of molecules you simply multiply the number of moles by 6.022 x 10^23.
1 mole is always equal to 6.022 x 10^23 no matter what element.
100.0 x 6.022 x 10^23 = 6.02 x 10^25
The answer only has three significant figures because 100.0 only has three.
