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:
it changes.
Explanation:
when in solid form it has an amount of mass. but when evaporated, water is pretty much massless.
When we describe properties of substances, we can divide them into chemical properties and physical properties. Chemical properties are how the substance react with other substances, while physical properties are mostly observable or measurable, which does not require the substance into reacting with other substances.
Since group I are all metals, the physical properties include shiny, malleable, ductile, good conductors of heat and electricity, have high melting points etc.
Chemical properties include react vigorously with water to form metal hydroxide and hydrogen, or react with oxygen to form metal oxide.
Answer:
480.40 g.
Explanation:
- According to the balanced equation:
<em>2 SO₂(g) + O₂(g) → 2 SO₃(g),</em>
it is clear that 2.0 moles of SO₂ react with 1.0 mole of oxygen to produce 2.0 moles of SO₃.
- We can get the no. of moles of SO₃ produced:
∵ 2.0 moles of SO₂ produce → 2.0 moles of SO₃, from the stichiometry.
∴ 6.0 moles of SO₂ produce → 6.0 moles of SO₃.
- Then, we can get the mass of the produced 6.0 moles of SO₃ using the relation:
<em>mass = no. of moles x molar mass of SO₃</em> = (6.0 moles)(80.066 g/mol) = <em>480.396 g ≅ 480.40 g.</em>