Mass/volume
In order to find density, you need to divide mass/volume
Answer:
We need 78.9 mL of the 19.0 M NaOH solution
Explanation:
Step 1: Data given
Molarity of the original NaOH solution = 19.0 M
Molarity of the NaOH solution we want to prepare = 3.0 M
Volume of the NaOH solution we want to prepare = 500 mL = 0.500 L
Step 2: Calculate volume of the 19.0 M NaOH solution needed
C1*V1 = C2*V2
⇒with C1 = the concentration of the original NaOH solution = 19.0 M
⇒with V1 = the volume of the original NaOH solution = TO BE DETERMINED
⇒with C2 = the concentration of the NaOH solution we want to prepare = 3.0 M
⇒with V2 = the volume of the NaOH solution we want to prepare = 500 mL = 0.500 L
19.0 M * V2 = 3.0 M * 0.500 L
V2 = (3.0 M * 0.500L) / 19.0 M
V2 = 0.0789 L
We need 0.0789 L
This is 0.0789 * 10^3 mL = 78.9 mL
We need 78.9 mL of the 19.0 M NaOH solution
B, D and E
Explanation:
conversion factors
1c = 8oz
1pt = 2c
1qt = 2pt
For A and B
ounces to cup = 160/8 = 20c
cup to pints = 20c / 2c = 10pt
pint to quarts = 10pt/2pt = 5qt
B applies as four 1-quart and two 1-pt = 5 1-quart
Considering C
4 8oz = 32oz
160-32 = 128oz /8 = 16c/2 = 8pints C does not apply
considering D
8 * 8 = 64oz
160 - 64 = 96oz/8 = 12c/2 = 6pt/2 = 3qt
So D applies
E applies