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3 years ago

The piece of solid metal can be described as

Chemistry

1 answer:

IRISSAK [1]3 years ago

6 0

Answer:

Explanation:

A piece of sodium metal can be described as

a pure substance and an element

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The center portion of the atom that contains the protons and neutrons is called the _____? nucleus

Virty [35]

It's called the atomic mass

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2 years ago

What is the molarity of a solution in which 7.1 g of sodium sulfate is dissolved in enough water to make 100. mL of solution?

Sidana [21]

Answer:

0.50 M

Explanation:

Given data

Mass of sodium sulfate (solute): 7.1 g

Volume of solution: 100 mL

Step 1: Calculate the moles of the solute

The molar mass of sodium sulfate is 142.04 g/mol. The moles corresponding to 7.1 grams of sodium sulfate are:

$7.1g \times \frac{1mol}{142.02g} = 0.050mol$

Step 2: Convert the volume of solution to liters

We will use the relation 1 L = 1000 mL.

$100mL \times \frac{1L}{1000mL} =0.100L$

Step 3: Calculate the molarity of the solution

$M = \frac{moles\ of\ solute }{liters\ of\ solution} = \frac{0.050mol}{0.100L} =0.50 M$

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2 years ago

Read 2 more answers

A buffer is prepared by dissolving honh2 and honh3no3 in some water. write equations to show how this buffer neutralizes added h

Anestetic [448]

Hydroxylamine in water: HONH₂(aq) + H₂O(l) ⇄ HONH₃⁺(aq) + OH⁻(aq).
Hydroxylammonium nitrate in water: HONH₃NO₃(aq) → OHNH₃⁺(aq) + NO₃⁻(aq).
1) with positive hydrogen ions (protons) react base and gives weak conjugate acid:
H⁺(aq) + HONH₂(aq) ⇄ HONH₃⁺(aq).
2) with hydroxide anions react acid and produce weak base and weak electrolyte water:
HONH₃⁺(aq) + OH⁻(aq) ⇄ HONH₂(aq) + H₂O(l).

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3 years ago

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For molecules with more than one ionizable groups, such as glycine, which of the following statements is true? For molecules wit

tester [92]

Answer: Option (a) is the correct answer.

Explanation:

The isoelectric point (pI) is actually the pH where a particular amino acid exists as a neutral molecule. This means that if pH equals pI then there will be no electric charge on the molecule.

Therefore, the statement at pH near the pI, nearly all the molecules carry no net charge, is true.

A buffer is composed of a solution of weak acid or base and salt of weak acid/base.So, when pH equals pI then there occurs no net charge. Hence, there will be no existence of conjugate acid-base pair.

Therefore, the statement when the pH is near the pI, the solution is near its maximum buffering ability, is false.

It is known that when pH is less than pI then there will be a net positive charge on the amino acid.

Hence, the statement at a pH near the pI, nearly all the molecules carry a net positive charge, is false.

When pH is greater than pI then amino acid will have a net negative charge. Hence, the statement at a pH near the pI, nearly all the molecules carry a net negative charge, is false.

Thus, we can conclude that out of the given options the statement at pH near the pI, nearly all the molecules carry no net charge, is true.

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3 years ago

For the Bradford assay, the instructor will make a Bradford reagent dye by mixing 50 ml of 95% v/v ethanol with 100 mg of Coomas

Flauer [41]

Answer:

4.25% is the final concentration of phosphoric acid.

Explanation:

Initial concentration of phosphoric acid = $C_1=85\%=0.85$