The answer is D.1.950 g
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Answer: D is right
Explanation: One mole contains 6.0225 ·10^23 molecules
Despite of the substance
Answer:
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Explanation:
The mass of the ice cubes and the water will be equal because the same amount of matter is in the beaker.
Matter is anything that has mass and occupy space. All substances are composed of matter. According to the law of conservation of mass, matter can neither be created nor destroyed but can be converted from one form to another.
Since mass is the quantity of matter in a substance, the mass of the ice cubes and the water will be equal because the same amount of matter is in the beaker.
Learn more: brainly.com/question/25150590
Answer:
2.25g of NaF are needed to prepare the buffer of pH = 3.2
Explanation:
The mixture of a weak acid (HF) with its conjugate base (NaF), produce a buffer. To find the pH of a buffer we must use H-H equation:
pH = pKa + log [A-] / [HA]
<em>Where pH is the pH of the buffer that you want = 3.2, pKa is the pKa of HF = 3.17, and [] could be taken as the moles of A-, the conjugate base (NaF) and the weak acid, HA, (HF). </em>
The moles of HF are:
500mL = 0.500L * (0.100mol/L) = 0.0500 moles HF
Replacing:
3.2 = 3.17 + log [A-] / [0.0500moles]
0.03 = log [A-] / [0.0500moles]
1.017152 = [A-] / [0.0500moles]
[A-] = 0.0500mol * 1.017152
[A-] = 0.0536 moles NaF
The mass could be obtained using the molar mass of NaF (41.99g/mol):
0.0536 moles NaF * (41.99g/mol) =
<h3>2.25g of NaF are needed to prepare the buffer of pH = 3.2</h3>
