Answer:
1.) 0.1 M
2.) 0.2 M
3.) 1 M
4.) Solution #3 is the most concentrated because it has the highest molarity. This solution has the largest solute to solvent ratio. The more solvent there is, the lower the concentration and molarity.
Explanation:
To find the molarity, you need to (1) convert grams NaOH to moles (via molar mass from periodic table) and then (2) calculate the molarity (via the molarity equation). All of the answers should have 1 sig fig to match the given values.
Molar Mass (NaOH): 22.99 g/mol + 16.00 g/mol + 1.008 g/mol
Molar Mass (NaOH): 39.998 g/mol
4 grams NaOH 1 mole
---------------------- x ------------------ = 0.1 moles NaOH
39.998 g
1.)
Molarity = moles / volume (L)
Molarity = (0.1 moles) / (1 L)
Molarity = 0.1 M
2.)
Molarity = moles / volume (L)
Molarity = (0.1 moles) / (0.5 L)
Molarity = 0.2 M
3.)
Molarity = moles / volume (L)
Molarity = (0.1 moles) / (0.1 L)
Molarity = 1 M
<span>6.12<span>(<span>1024</span>)</span></span><span>=<span><span>(6.12)</span><span>(<span><span>1e</span>+24</span>)</span></span></span><span>=<span><span>6.12e</span>+24</span></span>
<span>
=
</span>
Answer:
The compound has a molar mass of 78.4 g/mol
Explanation:
Step 1: data given
Mass of a sample = 0.5 grams
Mass of benzene = 25 grams
Freezing poing = 5 °C
Kf of benzene = 5.1 °C/m
Freezing point solution = 3.7 °C
Step 2: Calculate molality
ΔT = i*Kf*m
⇒with ΔT = the freezing point depression = 5.0 - 3.7 = 1.3 °C
⇒with i = the can't hoff factor = 1
⇒with Kf = the freezing point depression constant of benzene = 5.1 °C/m
⇒with m = the molality
1.3 = 5.1 * m
m = 1.3 / 5.1
m = 0.255 moles /kg
Step 3: Calculate moles
Molality = moles / mass benzene
0.255 molal = moles / 0.025 kg
Moles = 0.255 molal * 0.025 kg
Moles = 0.006375 moles
Step 4: Calculate molar mass of the compound
Molar mass compund = mass / moles
Molar mass compound = 0.5 grams / 0.006375 moles
Molar mass compound = 78.4 g/mol
The compound has a molar mass of 78.4 g/mol
Answer:
B. Alpha
Explanation:
Alpha decays always split into an element and He.
Beta decays always split into an element and e- (eletrons).
Gamma decays always split into an element and radiation.