Rearrange the Ideal Gas Law to this:
n = PV / RT
Substitute values into the equation:
<span>n = [ (750.0 mmHg / 760.0 mmHg atm¯1) (0.890 L) ] / (0.08206 L atm mol¯1 K¯1) (294.0 K)</span>
Answer:
Carbon is a chemical element, like hydrogen, oxygen, lead or any of the others in the periodic table. Carbon is a very abundant element. It exists in pure or nearly pure forms – such as diamonds and graphite – but can also combine with other elements to form molecules.
Answer Option D
Counting the number of atoms each side of the equation shows that the numbers balance.
Q=m°C<span>ΔT
=(500g) x (1 cal/g.</span>°C) x (48°C-21°C) = 13500 cal
13500 cal / 1000 = 13.5 kcal
<span>"What is the caloric value (kcal/g) of the french fries?"
13.5 kcal/ 2.5 g = 5.4 kcal/g</span>
Answer:
0.0102moles CaCl₂.2H₂O
0.0102moles CaCl₂
Explanation:
To convert moles to grams or vice versa of a compound, it is necessary to find molar mass of this substance.
For the CaCl₂.2H₂O:
This is the calcium chloride dihydrate (Because there are 2 molecules of water). That means you have 1 atom of Ca, 2 atoms of Cl, 4 atoms of H and 2 atoms of C. <em>Molar mass is the algebraic sum of the atomic weights that compose the molecule. </em>
Molar mass:
Ca: 1ₓ40.08g/mol = 40.08g/mol
Cl: 2ₓ35.45g/mol = 70.90g/mol
H: 4ₓ1.01g/mol: 4.04g/mol
O: 2ₓ16g/mol: 32g/mol.
40.08 + 70.90 + 4.04 + 32 = <em>147.02g/mol</em>
By using the molar mass of the susbtance, 1.50g are:
1.50g ₓ (1mol / 147.02g) =
<h3>0.0102moles CaCl₂.2H₂O</h3>
In the 1.50g of CaCl₂.2H₂O you have 0.0102 moles. As you can see, 1 mole of the dihydrate substance contains 1 mole of CaCl₂. Thus, you have:
<h3>0.0102moles CaCl₂</h3><h3 />