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3 years ago

What year did mendeleev organized his periodic table in order of increasing atomic number

Chemistry

1 answer:

ELEN [110]3 years ago

6 0

Mendeleev organized his periodic table in order of increasing atomic number in 1869.

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What is the percent-by-mass concentration of acetic acid (CH3COOH) in a vinegar solution that contains 51.80 g acetic acid in a

Semenov [28]

Answer : The percent-by-mass concentration of acetic acid is, 5.15 %

Explanation : Given,

Mass of acetic acid = 51.80 g

Density of solution = 1.005 g/ml

Volume of solution = 1.000 L = 1000 ml (1 L = 1000 ml)

First we have to calculate the mass of solution.

$\text{Mass of solution}=\text{Density of solution}\times \text{Volume of solution}$

$\text{Mass of solution}=1.005g/ml\times 1000ml=1005g$

Now we have to calculate the percent-by-mass concentration of acetic acid.

$\% \text{ by mass of acetic acid}=\frac{\text{Mass of acetic acid}}{\text{Mass of solution}}\times 100$

Now put all the given values in this formula, we get:

$\% \text{ by mass of acetic acid}=\frac{51.80g}{1005g}\times 100=5.15\%$

Therefore, the percent-by-mass concentration of acetic acid is, 5.15 %

6 0

3 years ago

What is the total number of molecules in 34.0?

mr Goodwill [35]

What is the element in which you are trying to find the number of molecules of?

7 0

3 years ago

What mass of solid that has a molar mass of 46.0 g/mol should be added to 150.0 g of benzene to raise the boiling point of benze

enyata [817]

Answer : 17.12 g

Explanation: $\Delta T =k_b\times m$

$\Delta T$ = elevation in boiling point

$k_b$ = boiling point elevation constant

m= molality

$molality=\frac{mass of solute}{molecular mass of solute\times weight of the solvent in kg}$

given $\Delta T=6.28^{\circ}C$

Molar mass of solute = 46.0 $gmol^{-1}$

Weight of the solvent = 150.0 g = 0.15 kg

Putting in the values

$molality=\frac{x}{46gmol^{-1}\times0.15kg}$

$6.28 =2.53^{\circ}Ckgmol^{-1}\frac{x}{46gmol^{-1}\times 0.15kg}$

x = 17.12 g

3 0

3 years ago

HELP WITH THIS ASAP PLEASE!!! What is the mass in grams of 8.42 x 10^22 atoms of sulfur?

V125BC [204]

Answer:

Answer:

see explanation and punch in the numbers yourself ( will be better for your test)

Explanation:

If you are given atoms you need to divide by Avogadro's number 6.022x10^23

then you will have moles of sulfur-- once you have moles multiply by the molar mass of sulfur to go from moles to grams

mm of sulfur is 32 g/mol

5 0

3 years ago

What is the energy released in this β − β − nuclear reaction 40 19 K → 40 20 C a + 0 − 1 e 19 40 K → 20 40 C a + − 1 0 e ? (The

Effectus [21]

<u>Answer:</u> The energy released in the given nuclear reaction is 1.3106 MeV.

<u>Explanation:</u>

For the given nuclear reaction:

$_{19}^{40}\textrm{K}\rightarrow _{20}^{40}\textrm{Ca}+_{-1}^{0}\textrm{e}$

We are given:

Mass of $_{19}^{40}\textrm{K}$ = 39.963998 u

Mass of $_{20}^{40}\textrm{Ca}$ = 39.962591 u

To calculate the mass defect, we use the equation:

$\Delta m=\text{Mass of reactants}-\text{Mass of products}$

Putting values in above equation, we get:

$\Delta m=(39.963998-39.962591)=0.001407u$

To calculate the energy released, we use the equation:

$E=\Delta mc^2\\E=(0.001407u)\times c^2$

$E=(0.001407u)\times (931.5MeV)$ (Conversion factor: $1u=931.5MeV/c^2$ )

$E=1.3106MeV$

Hence, the energy released in the given nuclear reaction is 1.3106 MeV.

6 0

3 years ago