Answer:
The equation for molarity is moles/liter for the first question you would do 0.256/0.143 liters to get 1.790 mol/L
Explanation:
The second problem you would do need to find the moles of NaCl which you would do by doing 4.89 g/58.44g/mol= 0.08367 then do 0.08367/0.600= 0.139 mol/L
The third problem would be the same steps as the second one.
The fourth problem would be (0.460M)(5.50L)= 2.53 moles
Percent error is the difference between the measured and known value, divided by the known value, multiplied by 100%.
So first, we take our measured value, .299 cm, minus our known value, .225 cm.
.299 cm - .225 cm=.004 cm
Next, we divide that by our known value
Finally, multiply your answer by 100
.0177777778 x 100= 1.77777778 %
Round to three significant figures, and you're done.
=1.78 % error
Answer:
0.645 L
Explanation:
To find the volume, you need to (1) convert grams to moles (using the molar mass) and then (2) calculate the volume (using the molarity ratio). The final answer should have 3 sig figs to match the sig figs of the given values.
(Step 1)
Molar Mass (KOH): 39.098 g/mol + 15.998 g/mol + 1.008 g/mol
Molar Mass (KOH): 56.104 g/mol
19.9 grams KOH 1 mole
-------------------------- x ----------------------- = 0.355 moles KOH
56.014 grams
(Step 2)
Molarity = moles / volume <----- Molarity ratio
0.550 M = 0.355 moles / volume <----- Insert values
(0.550 M) x volume = 0.355 moles <----- Multiply both sides by volume
volume = 0.645 L <----- Divide both sides by 0.550
The empirical formula : C₁₂H₄F₇
The molecular formula : C₂₄H₈F₁₄
<h3>Further explanation</h3>
mol C (MW=12 g/mol)
mol H(MW=1 g/mol) :
mol F(MW=19 g/mol)
mol ratio of C : H : O =1.52 : 0.51 : 0.89=3 : 1 : 1.75=12 : 4 : 7
Empirical formula : C₁₂H₄F₇
(Empirical formula)n=molecular formula
( C₁₂H₄F₇)n=562 g/mol
(12.12+4.1+7.19)n=562
(281)n=562⇒ n =2
Molecular formula : C₂₄H₈F₁₄
Answer:
4 boiling point elevation
