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3 years ago

2. When multiplying or dividing measured numbers, we use the measurement with the least number of

Chemistry

1 answer:

Goryan [66]3 years ago

4 0

Answer:

a. 105

b. 76.4

c. 0.04

d. 4.000

Explanation:

Question a. has three significant figures

Question b. has three significant figures

Question c. has one significant digit (only the 3 is significant in the question, zeros are only significant if they are trailing with the presence of a decimal point or in between two non-zero numbers)

Question d. has four significant figures

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How many molecules are in 9.40 moles of AICI3?

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The answer would 5.66 x 10 power of 24

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2. List and elaborate on at least two limitations of the 24-hour recall as a

Pavlova-9 [17]

Answer:

The correct answer is - may not be typical, and participant burden.

Explanation:

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3 years ago

one reaction that produces hydrogen gas can be represented by the unbalanced chemical equation Mg(s)+HCI(aq) -> MgCI(aq)+H2(g

Sonbull [250]

<h3>Answer:</h3>

128 g HCl

<h3>General Formulas and Concepts:</h3>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

Reading a Periodic Table

<u>Stoichiometry</u>

Reaction Mole Ratios
Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[RxN - Unbalanced] Mg (s) + HCl (aq) → MgCl (aq) + H₂ (g)

↓

[RxN - Balanced] 2Mg (s) + 2HCl (aq) → 2MgCl (aq) + H₂ (g)

[Given] 3.25 mol Mg

[Solve] x g HCl

<u>Step 2: Identify Conversions</u>

[RxN] 2 mol Mg → 2 mol HCl

[PT] Molar Mass of H - 1.01 g/mol

[PT] Molar Mass of Cl - 35.45 g/mol

Molar Mass of HCl - 1.01 + 35.45 = 36.46 g/mol

<u>Step 3: Stoich</u>

[S - DA] Set up: $\displaystyle 3.25 \ mol \ Mg(\frac{2 \ mol \ HCl}{2 \ mol \ Mg})(\frac{36.46 \ g \ HCl}{1 \ mol \ HCl})$
[S - DA] Multiply/Divide [Cancel out units]: $\displaystyle 127.61 \ g \ HCl$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 3 sig figs.</em>

127.61 g HCl ≈ 128 g HCl

3 0

3 years ago

PLEASE HELP I NEED IT!!!!!

galina1969 [7]

Answer:
Molarity = 2.3 M

Explanation:
Molarity can be calculated using the following rule:
Molarity = number of moles of solute / volume of solution

1- getting the number of moles:
We are given that:
mass of solute = 105.96 grams
From the periodic table:
atomic mass of carbon = 12 grams
atomic mass of hydrogen = 1 gram
atomic mass of oxygen = 16 grams
Therefore:
molar mass of C2H6O = 2(12) + 6(1) + 16 = 46 grams
Now, we can get the number of moles as follows:
number of moles = mass / molar mass = 105.96 / 46 = 2.3 moles

2- The volume of solution is given = 1 liter

3- getting the molarity:
molarity = number of moles of solute / volume of solution
molarity = 2.3 / 1
molarity = 2.3 M

Hope this helps :)

8 0

3 years ago