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3 years ago

What is the percent by mass of oxygen in ca(oh)2? [formula mass = 74.1]

Chemistry

2 answers:

andre [41]3 years ago

8 0

16(2)/74.1=.431

.431x100= 43.1%

finlep [7]3 years ago

8 0

Answer:

43.18%

Explanation:

To calculate the percentage by mass of oxygen in the compound, multiply the atomic mass of oxygen by two. This is done because the compound contains two moles of oxygen.

16*2=32

32 divided by the formula mass as given in the question multiplied by 100 gives 43.18%

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yaroslaw [1]

10 is mixture of elements and compounds
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3 years ago

Silver sulfate (Ag2SO4) is slightly soluble in water and it partly dissolves at the equilibrium according to the following balan

natka813 [3]

Answer:

a) S = 0.0152 mol/L

b) S' = 4.734 g/L

Explanation:

Ag2SO4 ↔ 2Ag+ + SO42-

S 2S S...............in the equilibrium

Ksp = 1.4 E-5 = [ Ag+ ]² * [ SO42-]

a) molar solubility:

⇒ Ksp = ( 2S) ² * S = 1.4 E-5

⇒ 4S² * S = 1.4 E-5

⇒ S = ∛ ( 1.4 E-5 / 4 )

⇒ S = 0.0152 mol/L

b) solubility ( S' ) in grams per liter:

∴ Mw Ag2SO4 = 311.799 g/mol

⇒ S' = 0.0152 mol/L * ( 311.799 g/mol )

⇒ S' = 4.734 g/L

4 0

3 years ago

Question 6

kompoz [17]

Considering the combined law equation, the new temperature is -244.56 °C or 28.44 K.

<h3>Boyle's law</h3>

Boyle's law states that the pressure of a gas in a closed container is inversely proportional to the volume of the container, when the temperature is constant: if the pressure increases, the volume decreases while if the pressure decreases, the volume increases.

Mathematically, this law states that the multiplication of pressure by volume is constant:

P×V=k

<h3>Charles's law</h3>

Charles's law states that the volume is directly proportional to the temperature of the gas: if the temperature increases, the volume of the gas increases while if the temperature of the gas decreases, the volume decreases.

Mathematically, Charles' law states that the ratio of volume to temperature is constant:

$\frac{V}{T} =k$

<h3>Gay-Lussac's law </h3>

Gay-Lussac's law states that the pressure of a gas is directly proportional to its temperature: increasing the temperature will increase the pressure, while decreasing the temperature will decrease the pressure.

Mathematically, Gay-Lussac's law states that the ratio of pressure to temperature is constant:

$\frac{P}{T} =k$

<h3>Combined law equation</h3>

Combined law equation is the combination of three gas laws called Boyle's, Charlie's and Gay-Lusac's law:

$\frac{PxV}{T} =k$

Considering an initial state 1 and a final state 2, it is fulfilled:

$\frac{P1xV1}{T1} =\frac{P2xV2}{T2}$

<h3>New temperature</h3>

In this case, you know:

P1= 1 atm= 760 mmHg
V1= 15 L
T1= -30 °C= 243 K (being 0 °C= 273 K)
P2= 58 mmHg
V2= 23 L
T2= ?

Replacing in the combined law equation:

$\frac{760 mmHgx15 L}{243 K} =\frac{58 mmHgx23 L}{T2}$

Solving:

$T2x\frac{760 mmHgx15 L}{243 K} =58 mmHgx23 L$

$T2 =\frac{58 mmHgx23 L}{\frac{760 mmHgx15 L}{243 K}}$

Finally, the new temperature is -244.56 °C or 28.44 K.

Learn more about combined law equation:

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6 0

2 years ago

Which of the following could be the rate equation for a first order reaction? please help this is timed

wel

Rate = k[A] = first order reaction

<h3>Further explanation</h3>

Given

Rate law

Required

A first-order reaction

Solution

The rate law : equation for the rate of chemical reaction

For reaction

aA + bB ⇒ C

The rate : r = k[A]ᵃ[B]ᵇ

The sum of exponents(a+b) is the reaction order

From the choice :

a. a+b = 2, second order reaction

b. a+b = 3, third order reaction

c. a+b = 4, fourth order reaction

d a+0 = 1, first order reaction

7 0

3 years ago

Which is the balanced equation for S₈+ O₂ → SO₂?

KiRa [710]

Answer:

D S8 + 802 - 8SO2

Explanation:

8* 2 =16

8*1=8

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3 years ago