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4 years ago

What molality of a nonvolatile, nonelectrolyte solute is needed to raise the boiling point of water by 7.10°c (kb = 0.520°c/m)?

1 answer:

7 0

According to boiling point elevation equation:
Δ T = i Kb m
when ΔT (change in boiling point) = 7.10 C°
and i (van't Hoff factor)= 1
and Kb = 0.520
so, by substitution:
7.10 = 1*0.520 *m
m = 7.1 / 0.52 = 13.65 m

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Which coefficients correctly balance the formula equation cao + h2o ® ca(oh)2?

djverab [1.8K]

CaO + H2O → Ca(OH)2

the number of O atom on the left side is 1 and on the right side 2 so,

we put 2H2O instead of H2O

CaO + 2H2O → Ca(OH)2

now we have to put 2Ca(OH)2 instead of Ca(OH)2 to make H atoms equal on both sides 4

CaO + 2H2O → 2Ca(OH)2

now we have to put 2CaO instead of CaO to make Ca atoms equal on both sides 2 atoms.

∴ the final balanced equation is:

2CaO + 2H2O → 2 Ca(OH)2

∴ the coefficients are 2 2 2

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3 years ago

How is salt obtained or manufactrured

Novay_Z [31]

Answer:

There are three methods used to produce salt: solar, evaporation and rock mining.

Explanation:

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3 years ago

If a car traveling 85.0 kilometers per hour how many feet will it travel in 5.00 seconds

Maslowich

The car will travel 387 ft in 5.00 s.

No. of kilometres = 5.00 s × (1 min/60 s) × (1 h/60 min) × (85.0 km/h) = 0.1181 km

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4 0

4 years ago

How many CaF are in a 1.7x10^25 please I need help fast!!

Gemiola [76]

<h3>Answer:</h3>

28 mol CaF

<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>

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[Given] 1.7 × 10²⁵ molecules CaF

[Solve] moles CaF

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

Avogadro's Number

<u>Step 3: Convert</u>

[DA] Set up: $\displaystyle 1.7 \cdot 10^{25} \ molecules \ CaF(\frac{1 \ mol \ CaF}{6.022 \cdot 10^{23} \ molecules \ CaF})$
[DA] Multiply/Divide [Cancel out units]: $\displaystyle 28.2298 \ moles \ CaF$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 2 sig figs.</em>

28.2298 mol CaF ≈ 28 mol CaF

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3 years ago

Find the volume of an object that has a mass of 20g and density of 184 glcm

expeople1 [14]

Volume= Mass/ Density= 20/184
= 0.108 cubic cm

8 0

3 years ago