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3 years ago

How many atoms are in 2.10 g of K? molar mass of K=39.10g/mole.

Chemistry

1 answer:

Alborosie3 years ago

5 0

Answer:

<h3>The answer is option B</h3>

Explanation:

To calculate the number of atoms we must first calculate the number of moles

Molar mass = mass / number of moles

number of moles = mass / Molar mass

Molar mass (K) = 39.10mole

mass = 2.10g

number of moles = 2.10/ 39.10

= 0.0537mol

After that we use the formula

N = n × L

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10^23 entities

Number of K atoms is

N = 0.0537 × 6.02 × 10^13

<h3>N = 3.23×10^22 atoms of K</h3>

Hope this helps you.

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monitta

Answer:

substrate-level phosphorylation

Explanation:

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3 years ago

The ksp of copper(ii) carbonate, cuco3, is 1.4 × 10-10. calculate the molar solubility of this compound.

mafiozo [28]

As,
CuCO₃   ⇆ Cu²⁺ + CO₃²⁻
So,
Kc = [Cu²⁺] [CO₃²⁻] / CuCO₃
Or,
Kc (CuCO₃) = [Cu²⁺] [CO₃²⁻]
Or,
Ksp = [Cu²⁺] [CO₃²⁻]
As,
Ksp = 1.4 × 10⁻¹⁰
So,
1.4 × 10⁻¹⁰ = [x] [x]
Or,
x² =  1.4 × 10⁻¹⁰
Or,
x = 1.18 × 10⁻⁵ mol/L
To cahnge ito g/L,
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3 years ago

2. How much heat is released when 432g of water cools down from 710C to 180C?

nadya68 [22]

The heat released by the water when it cools down by a temperature difference AT

is Q = mC,AT

where

m=432 g is the mass of the water

C, = 4.18J/gºC

is the specific heat capacity of water

AT = 71°C -18°C = 530

is the decrease of temperature of the water

Plugging the numbers into the equation, we find

Q = (4329)(4.18J/9°C)(53°C) = 9.57. 104J

and this is the amount of heat released by the water.

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3 years ago

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Vanyuwa [196]

Answer:

True

Explanation:

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3 years ago

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