The answer is 9.03 × 10²⁴<span> molecules.
</span><span>Avogadro's number is the number of units (atoms, molecules) in 1 mole of substance.
Make the proportion.
</span><span>6.02 × 10²³ molecules per 1 mol
</span>x per 15 mol
6.02 × 10²³ molecules : 1 mol = x : 15 mol
x = 6.02 × 10²³ molecules * 15 mol * 1 mol
x = 90.3 × 10²³ molecules
x = 9.03 × 10 × 10²³ molecules
x = 9.03 × 10²³⁺¹ molecules
x = 9.03 × 10²⁴ molecules
Answer:
0.60 moles of Na₂SO₄
Explanation:
Molarity is an unit of concentration defined as the ratio between moles of solute and liters of solution.
A solution of Na₂SO₄ 0.40M contains 0.40 moles of solute (Na₂SO₄) per liter of solution.
As you have 1.5L of solution, moles of Na₂SO₄:
1.5L × (0.40mol / L) = <em>0.60 moles of Na₂SO₄</em>
Answer:
D H2PO4– + HPO42–
Explanation:
The acid dissociation constant for 
are 
respectively.
The reason while option D is the best answer is that, the value of pKa for both
lies on either side of the desired pH of the buffer. This implies that one is slightly over and the other is slightly under.
Using Henderson-Hasselbach equation:
The period of the life cycle during which positive nitrogen balance is most likely to occur is childhood.
<h3>What is nitrogen balance?</h3>
The term nitrogen balance refers to the fact that there is a balance between the intake and the loss of nitrogen. The intake of nitrogen occurs when a person takes in food that contain proteins which are a rich source of nitrogen in the body and helps in the process of the build up of the cells in the body.
The period of the life cycle during which positive nitrogen balance is most likely to occur is childhood.
Learn more about nitrogen balance:brainly.com/question/14570903
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The amount of heat required to purify the Al is 25.94 * 10^3 J
<h3>What is heat capacity?</h3>
The term heat capacity refers to the amount of heat required to raise the temperature of a substance by 1K. The aluminum was heated from 298 K to 933 K then it melted.
The total heat required is;
H = ncdT + nL
H = (1 * 24 * (933 - 298)) + (1 * 10.7 * 10^3)
H = 15.24 * 10^3 J + 10.7 * 10^3 J
H = 25.94 * 10^3 J
Learn more about heat capacity: brainly.com/question/1453843
