WILL GIVE BRAINLIEST!

1.Which of the following are considered pure substances

PilotLPTM [1.2K]

1.) homogeneous mixtures

2.) NaCI, because sodium is a metal and chlorine is a nonmetal

3.) I'm thinking the first the option

5 0

2 years ago

when you started the activity, the can was open to the air outside tge can. how did the air pressure inside the can compare to t

aliya0001 [1]

The air pressure inside the can is lower compared to that of outside air pressure.

Explanation:

In general, the air pressure of an already opened can will be the same as the outside pressure.
Since the can is evacuated and remain as vacuum, so there will be no pressure difference in it.
If the can opens, air inside the can push the top and escapes to the outside.
This is due to high pressure experienced outside the can compare to that of lower pressure inside the can and this may even cause can to collapse itself.

7 0

2 years ago

Jai besoi daide

JulijaS [17]

Answer:

i dont know what you are saying

Explanation:

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4 0

2 years ago

Analysis of a gaseous chlorofluorocarbon, CClxFy, shows that it contains 11.79% C and 69.57% Cl. In another experiment, you find

uranmaximum [27]

Answer:

The molecular formula = $C_2Cl_{4}F_2$

Explanation:

$Moles =\frac {Given\ mass}{Molar\ mass}$

% of C = 11.79

Molar mass of C = 12.0107 g/mol

% moles of C = 11.79 / 12.0107 = 0.9816

% of Cl = 69.57

Molar mass of Cl = 35.453 g/mol

% moles of Cl = 69.57 / 35.453 = 1.9623

Given that the gaseous chlorofluorocarbon only contains chlorine, flourine and carbon. So,

% of F = 100% - % of C - % of C = 100 - 11.79 - 69.57 = 18.64

Molar mass of F = 18.998 g/mol

% moles of F = 18.64 / 18.998 = 0.9812

Taking the simplest ratio for C, Cl and F as:

0.9816 : 1.9623 : 0.9812

= 1 : 2 : 1

The empirical formula is = $CCl_2F$

Also, Given that:

Pressure = 21.3 mm Hg

Also, P (mm Hg) = P (atm) / 760

Pressure = 21.3 / 760 = 0.02803 atm

Temperature = 25 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (25 + 273.15) K = 298.15 K

Volume = 458 mL = 0.458 L (1 mL = 0.001 L)

Using ideal gas equation as:

PV=nRT

where,

P is the pressure

V is the volume

n is the number of moles

T is the temperature

R is Gas constant having value = 0.0821 L.atm/K.mol

Applying the equation as:

0.02803 atm × 0.458 L = n × 0.0821 L.atm/K.mol × 298.15 K

⇒n = 0.00052445 moles

Given that :

Amount = 0.107 g

Molar mass = ?

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$0.00052445= \frac{0.107\ g}{Molar\ mass}$

$Molar\ mass= 204.0233\ g/mol$

Molecular formulas is the actual number of atoms of each element in the compound while empirical formulas is the simplest or reduced ratio of the elements in the compound.

Thus,

Molecular mass = n × Empirical mass

Where, n is any positive number from 1, 2, 3...

Mass from the Empirical formula = 1×12.0107 + 2×35.453 + 1×18.998 = 101.9147 g/mol

Molar mass = 204.0233 g/mol

So,

Molecular mass = n × Empirical mass

204.0233 = n × 101.9147

⇒ n = 2

The molecular formula = $C_2Cl_{4}F_2$

6 0

3 years ago

How much heat will be released when 10.0 g of hydrogen peroxide decomposes according to the following reaction: 2H2O2(l) 2H2O(l)

kramer

C. 28 KJ

AMU of H2O2 = 2(1) + 2(16) = 34 g/mol
10 g / 34 g/mol = 0.294 mol H2O2

0.294 mol / H = 2 mol / 190 KJ
H = 28.9 KJ

5 0

3 years ago