Answer:
0.429 M
Explanation:
To find the molarity, you need to (1) convert grams to moles (using the molar mass), then (2) convert mL to L, and then (3) calculate the molarity (using the molarity ratio).
(Step 1)
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
18.8 grams NaCl 1 mole
-------------------------- x ------------------------ = 0.322 moles NaCl
58.443 grams
(Step 2)
1,000 mL = L
750.0 mL 1 L
------------------ x ----------------- = 0.7500 L
1,000 mL
(Step 3)
Molarity (M) = moles / volume (L)
Molarity = 0.332 moles / 0.7500 L
Molarity = 0.429 M
Answer:
85.5%
Explanation:
To get the experimental value, you need to convert 15.0 grams of Na2SO4 to grams of Na3PO4. You do this with stoichiometry.
Convert grams of Na2SO4 to moles with molar mass. Then convert to moles of Na3PO4 with the mole-to-mole ratio according to the balanced chemical equation. Then convert moles of Na3PO4 to grams with the molar mass.
15.0 g Na2SO4 x (1 mol/142.04 g) x (2 Na3PO4/3Na2SO4) x (163.94 g/1 mol) = 11.7 g Na3PO4
Percent Yield = (actual value/experimental value) x 100
Actual Value = 10.0 g
Experimental Value = 11.7 g
10.0g/11.7 g = 85.5%
Physical change because the matter in the object is not chemically changing
It DOES contain ionic bonds because covalent can’t dissolve in water or conduct electricity. The substance will not contain covalent bonds.
