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3 years ago

13

What is the atomic number of this element?

1 answer:

Illusion [34]3 years ago

5 0

Answer:

27

Explanation:

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according to iupac nomeclature rules which set of chemical name and formula for the same compound is correct?

kumpel [21]

Answer:

stock and traditional

Explanation:

the iupac says so

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2 years ago

The bond type in CaO is

sergey [27]

CaO is an ionic bond

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3 years ago

What is the relationship between mole, Avogadro number and mass?

weeeeeb [17]

Answer:

The mass of one mole of a substance is equal to that substance's molecular weight. ... water is 18.015 atomic mass units (amu), so one mole of water weight 18.015 grams. ... Avogadro's number is a proportion that relates molar mass on an atomic ... one molecule of water (H2O), one mole of oxygen (6.022×1023 of O atoms)

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2 years ago

Elis [28]

The answer should be 502

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3 years ago

Start with 100.00 mL of 0.10 M acetic acid, CH3COOH. The solution has a pH of 2.87 at 25 oC. a) Calculate the Ka of acetic acid

jasenka [17]

Answer: a) The $K_a$ of acetic acid at $25^0C$ is $1.82\times 10^{-5}$

b) The percent dissociation for the solution is $4.27\times 10^{-3}$

Explanation:

$CH_3COOH\rightarrow CH_3COO^-H^+$

cM 0 0

$c-c\alpha$ $c\alpha$ $c\alpha$

So dissociation constant will be:

$K_a=\frac{(c\alpha)^{2}}{c-c\alpha}$

Give c= 0.10 M and $\alpha$ = ?

Also $pH=-log[H^+]$

$2.87=-log[H^+]$

$[H^+]=1.35\times 10^{-3}M$

$[CH_3COO^-]=1.35\times 10^{-3}M$

$[CH_3COOH]=(0.10M-1.35\times 10^{-3}=0.09806M$

Putting in the values we get:

$K_a=\frac{(1.35\times 10^{-3})^2}{(0.09806)}$

$K_a=1.82\times 10^{-5}$

b) $\alpha=\sqrt\frac{K_a}{c}$

$\alpha=\sqrt\frac{1.82\times 10^{-5}}{0.10}$

$\alpha=4.27\times 10^{-5}$

$\% \alpha=4.27\times 10^{-5}\times 100=4.27\times 10^{-3}$

5 0

3 years ago