Ask question

Ask question

All categories

3 years ago

7

HELP PLZ!!! A sample contains only the compound CaCl2 and water. When it is dried, its weight decreases from 5.00g to 4.24g. Wha

t is the mass percentage of water in the original sample? Round to three significant figures.

2 answers:

steposvetlana [31]3 years ago

7 0

Answer:

Mass of water is 18.01528 g/mol. I hope this helps

Explanation:

AfilCa [17]3 years ago

5 0

Answer:is 15.2%

Explanation:

Got it wrong and this the correct answer it told me

You might be interested in

The substances that start a chemical reaction are called?

Ber [7]

Answer: The reactants

Explanation: These are the substances that go into a chemical reaction and start it.

6 0

3 years ago

Read 2 more answers

The density of no2 in a 4.50 l tank at 760.0 torr and 25.0 Â°c is ________ g/l.

kap26 [50]

From ideal gas equation that is PV=nRT
n(number of moles)=PV/RT
P=760 torr
V=4.50L
R(gas constant =62.363667torr/l/mol
T=273 +273=298k
n is therefore (760torr x4.50L) /62.36367 torr/L/mol x298k =0.184moles
the molar mass of NO2 is 46 therefore density= 0.184 x 46=8.464g/l

7 0

3 years ago

Read 2 more answers

Chemistry: Gas Laws Problems!

Ronch [10]

Answer : The final volume at STP is, 1000 L

Explanation :

According to the Boyle's, law, the pressure of the gas is inversely proportional to the volume of gas at constant temperature and moles of gas.

$P\propto \frac{1}{V}$

or,

$P_1V_1=P_2V_2$

where,

$P_1$ = initial pressure = 1520 mmHg = 2 atm (1 atm = 760 mmHg)

$P_2$ = final pressure at STP = 1 atm

$V_1$ = initial volume = 500.0 L

$V_2$ = final volume at STP = ?

Now put all the given values in the above formula, we get:

$2atm\times 500.0L=1atm\times V_2$

$V_2=1000L$

Therefore, the final volume at STP is, 1000 L

7 0

3 years ago

According to Newton's First Law of Motion, what does it take to move an object at rest?

Rufina [12.5K]

I'm pretty sure the answer is B double check to make sure it isn't A

6 0

3 years ago

A sample of an unknown biochemical compound is found to have a percent composition of 45.46 percent carbon, 7.63 percent hydroge

Leona [35]

Answer:

Formular = C₅H₁₁NO₃

Explanation:

The empirical formular is the simplest formular of a compound can have.

We use the steps below to obtain the empirical formular;

Step 1: Obtain the mass of each element present in grams. Element % = mass in g = m.

Carbon = 45.46% = 45.46g

Hydrogen = 7.63% = 7.63g

Nitrogen = 10% = 10g

Oxygen = 100% - (45.46% + 7.63% + 10%) = 36.31% = 36.31g

Step 2: Determine the number of moles of each type of atom present.

Molar amount (M) = m/atomic mass

Carbon = 45.46 / 12 = 3.7883

Hydrogen = 7.63 / 1 = 7.63

Nitrogen = 10 / 14 = 0.7143

Oxygen = 36.91 / 16 = 2.3069

Step 3: Divide the number of moles of each element by the smallest number of moles. Smallest = 0.7143

Carbon = 3.7883 / 0.7143 = 5.3035

Hydrogen = 7.63 / 0.7143 = 10.67

Nitrogen = 0.7143 / 0.7143 = 1

Oxygen = 2.2693 / 0.7143 = 3.1770

Step 4: Convert numbers to whole numbers

Carbon = 5

Hydrogen = 11

Nitrogen = 1

Oxygen = 3

Formular = C₅H₁₁NO₃

3 0

4 years ago