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2 years ago

Calculate the atoms of hydrogen in 52.0 g of H2O.

Chemistry

1 answer:

Zarrin [17]2 years ago

5 0

Answer:

34.81 ×10²³ atoms

Explanation:

Given data:

Mass of water = 52.0 g

Number of atoms of hydrogen = ?

Solution:

Number of moles of water:

Number of moles = mass/molar mass

Number of moles = 52.0 g/ 18 g/mol

Number of moles = 2.89 mol

1 mole of water contain 2 mole of hydrogen.

2.89 mole of water contain 2.89× 2= 5.78 moles of hydrogen.

Number of atoms of hydrogen:

1 mole = 6.022×10²³ atoms

5.78 mol × 6.022×10²³ atoms / 1mol

34.81 ×10²³ atoms

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Explain the digestive process in an essay.

fiasKO [112]

Refer to attachment for your answer

8 0

2 years ago

In the following reaction, 451.4 g of lead reacts with excess oxygen forming 365.0 g of lead(II) oxide. Calculate the percent yi

user100 [1]

Let MM(x) be the molar mass of x.

MM(Pb) : MM(PbO)
=207.21 : 223.20 = 451.4 g : x g

cross multiply and solve for x
x=223.2/207.21*451.4
= 486.23 g

Percentage yield = 365.0/486.23= 0.75067 = 75.07% (rounded to 4 sign. fig.)

4 0

3 years ago

When a lead acid car battery is recharged by the alternator, it acts essentially as an electrolytic cell in which solid lead(II)

katen-ka-za [31]

Answer:

3.81 g Pb

Explanation:

When a lead acid car battery is recharged, the following half-reactions take place:

Cathode: PbSO₄(s) + H⁺ (aq) + 2e⁻ → Pb(s) + HSO₄⁻(aq)

Anode: PbSO₄(s) + 2 H₂O(l) → PbO₂(s) + HSO₄⁻(aq) + 3H⁺ (aq) + 2e⁻

We can establish the following relations:

1 A = 1 c/s
1 mole of Pb(s) is deposited when 2 moles of e⁻ circulate.
The molar mass of Pb is 207.2 g/mol
1 mol of e⁻ has a charge of 96468 c (Faraday's constant)

Suppose a current of 96.0A is fed into a car battery for 37.0 seconds. The mass of lead deposited is:

$37.0s.\frac{96.0c}{s} .\frac{1mole^{-} }{96468c} .\frac{1molPb}{2mole^{-} } .\frac{207.2gPb}{1molPb} =3.81gPb$

6 0

3 years ago

Determine the heat energy needed to raise the temperature of 120 grams of ice at -5 to steam at 115°

CaHeK987 [17]

Answer:

Q = 30355.2 J

Explanation:

Given data:

Mass of ice = 120 g

Initial temperature = -5°C

Final temperature = 115°C

Energy required = ?

Solution:

Specific heat capacity of ice is = 2.108 j/g.°C

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

Q = m.c. ΔT

ΔT = T2 -T1

ΔT = 115 - (-5°C)

ΔT = 120 °C

Q = 120 g × 2.108 j/g.°C × 120 °C

Q = 30355.2 J

5 0

3 years ago

A solution prepared by dissolving 0.100 mole of propionic acid in enough water to make 1.00 L of solution is observed to have a

torisob [31]

Answer:

C) $k_a=1.3\times 10^{-5}$

Explanation:

pH is defined as the negative logarithm of the concentration of hydrogen ions.

Thus,

pH = - log [H⁺]

The expression of the pH of the calculation of weak acid is:-

$pH=-log(\sqrt{k_a\times C})$

Where, C is the concentration = 0.5 M

Given, pH = 2.94

Moles = 0.100 moles

Volume = 1.00 L

So, $Molarity=\frac{Moles}{Volume}=\frac{0.100}{1.00}\ M=0.100\ M$

C = 0.100 M

$2.94=-log(\sqrt{k_a\times 0.100})$

$\log _{10}\left(\sqrt{k_a0.1}\right)=-2.94$

$\sqrt{0.1}\sqrt{k_a}=\frac{1}{10^{2.94}}$

$k_a=1.3\times 10^{-5}$

4 0

3 years ago