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3 years ago

How many molecules in 4.10 mol H2O?

Chemistry

1 answer:

Shtirlitz [24]3 years ago

8 0

Answer:

2,47 * $10^{24}$ (molecules)

Explanation:

Avogadro's number is a very important relationship: 1 mole = 6,02 * $10^{23}$ atoms, molecules, protons, etc.

To convert from moles to molecules, multiply the molar amount by Avogadro's number.

4,1 mol * 6,02 * $10^{23}$ ≈ 24,7 * $10^{23}$ = 2,47 * $10^{24}$ (molecules)

Therefore the third answer is correct

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myrzilka [38]

Answer:

Molar Mass

Explanation:

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3 years ago

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Fernando places 50 mL of HCl in a 100 mL beaker and 50 mL of NaOH in a 100 mL beaker. he places them on a scale together and mea

olchik [2.2K]

Answer:

The correct options are:

B. The HCl is the solute.

D. The H₂O is the solvent.

E. This mixture conducts electricity.

Explanation:

For the preparation of the HCl solution, 10 mL of HCl and 40 mL of water were mixed.

The compound that is present in the solution in a smaller ratio is the solute and the other compount -present in higher ratio- is the solvent.

So, the solute is HCl and the solvent is water (H₂O). Furthermore, water is considered as an universal solvent (for most of the polar and ionic compounds). According to this, the following options are correct:

B. The HCl is the solute.

D. The H₂O is the solvent.

Then, a condition for a solution that is able to conduct electricity is the presence of ions in the solution. When HCl is dissolved in water, it dissociates in ions according to the following equilibrium:

HCl ⇔ H⁺ + Cl⁻

The ions H⁺ and Cl⁻ are electrically charged so the solution can conduct electricity. According to this, the following option is also correct:

E. This mixture conducts electricity.

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3 years ago

You are given an unknown type of clothing dye. How could you use the procedures in this lab to see if this dye is a mixture? Ple

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To find out if a dye is a mixture or not, you can make use of the chromatography method of separation.
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3 years ago

(Help!) What is the mass of hydrogen atoms that is measured at 72 u?

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Answer:

=71.439911 u

Explanation:

We know that 1 mass of hydrogen atom = 1.00784 u

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2 years ago

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How much potassium nitrate has to dissolve in water to absorb 105 kj of heat? there are 4.184 kj/kcal. also note the answer is t

joja [24]

Lattice energy of potassium nitrate (KNO3) = -163.8 kcal/mol

Hydration energy of KNO3 = -155.5 kcal/mole

Heat of solution is the amount of heat absorbed by water when 1 mole of KNO3 is dissolved in it

Heat of solution = Hydration energy - Lattice energy

= -155.5 -(-163.8) = 8.3 kcal/mol

1 kcal/mol = 4.184 kJ/mole

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4 years ago