Answer:
8.8g of Al are necessaries
Explanation:
Based on the reaction, 2 moles of Al are required to produce 3 moles of hydrogen gas.
To solve this question we must find the moles of H2 in 11L at STP using PV = nRT. With these moles we can find the moles of Al required and its mass as follows:
<em>Moles H2:</em>
PV = nRT; PV/RT = n
<em>Where P is pressure = 1atm at STP; V is volume = 11L; R is gas constant = 0.082atmL/molK and T is absolute temperature = 273.15K at STP</em>
Replacing:
1atm*11L/0.082atmL/molK*273.15K = n
n = 0.491 moles of H2 must be produced
<em />
<em>Moles Al:</em>
0.491 moles of H2 * (2mol Al / 3mol H2) = 0.327moles of Al are required
<em />
<em>Mass Al -Molar mass: 26.98g/mol-:</em>
0.327moles of Al * (26.98g / mol) = 8.8g of Al are necessaries
Answer:
D.
Explanation:
Deciding whether the best product has been designed,should be the last step.
Answer:
The pressure builds up
Explanation:
Pressure gets hotter and hotter as it is squeezed together and the molecules go faster and creates more energy and ultimately more heat
According to the balanced reaction equation:
2KClO3→ 2KCl + 3O2
from this equation, we can see that the molar ratio between KCl & O2 is 2 : 3
so, 2 moles of KCl will need 3 moles of O2
∴ 7.16 moles of KCl will need X moles of O2
∴number of moles of O produced = 7.16 * 3 / 2
= 10.74 moles
Answer:
Ca(aq)⁺² + CO₃⁻²(aq) → CaCO₃(s)
Explanation:
Breaking down the equation into ionic form gives:
2Na⁺(aq) + CO₃⁻²(aq) + Ca⁺²(aq) + 2NO₃⁻¹ (aq) → 2Na⁺(aq) + 2NO₃⁻¹(aq) + CaCO₃(s)
Eliminating all the same ionic states on both sides of the equation gives following final equation
Ca(aq)⁺² + CO₃⁻²(aq) → CaCO₃(s)