<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7B2.568%20%5Ctimes%205.8%7D%7B4.186%7D%20" id="TexFormula1" title=" \frac{2.568 \ti

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2 years ago

mes 5.8}{4.186} " alt=" \frac{2.568 \times 5.8}{4.186} " align="absmiddle" class="latex-formula">
Round off the answer to the correct number of significant figures:

Chemistry

1 answer:

melomori [17]2 years ago

3 0

Using a calculator:

(2.568 x 5.8)/4.186 = 3.5581460…
= 3.56 (3sf)

You didn’t specify the correct number of significant figures needed.

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9. During an experiment the students prepared three mixtures A)Starch in water B) Sodium chloride solution C) Tincture of Iodine

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Answer:

See explanation

Explanation:

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In tincture of iodine, the size of particles in solution is less than 1 nm in diameter hence the solution does not exhibit Tyndall effect. Hence, tincture of iodine is a true solution.

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2 years ago

When solving an equation using Gay-Lussac's law, which of the following steps do not apply? A. List your knowns and unknowns. B.

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Answer:

C. Plug the unknowns into the ideal gas law formula.

Explanation:

Gay-Lussac's law states that:

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Mathematically, it can be written as:

$\frac{p_1}{T_1}=\frac{p_2}{T_2}$

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p1 is the initial pressure

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p2 is the final pressure

T2 is the final temperature (in Kelvin)

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3 years ago

How many moles of calcium carbonate-CaCO3 = 4.15 g

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Answer:

Number of moles = 0.042 mol

Explanation:

Given data:

Number of moles = ?

Mass of calcium carbonate = ?

Solution:

Formula:

Number of moles = mass/ molar mass

now we will calculate the molar mass of calcium carbonate.

atomic mass of Ca = 40 amu

atomic mass of C = 12 amu

atomic mass of O = 16 amu

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Number of moles = 4.15 g / 100 g/mol

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3 years ago

NH3 is a weak base (Kb = 1.8 × 10–5) and so the salt NH4Cl acts as a weak acid. What is the pH of a solution that is 0.084 M in

kolbaska11 [484]

Answer is: pH of solution is 5,17.
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3 years ago