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Deffense [45]
3 years ago
7

James Watson and Francis Crick _____.

Chemistry
2 answers:
Mashutka [201]3 years ago
6 0
The answer is D because Franklin was the one who discovered it but could present it because she passed away
Dimas [21]3 years ago
3 0

Answer:

b

Explanation:

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All the substances listed below are fertilizers that contribute nitrogen to the soil.
kvv77 [185]

Answer:

Ammonia is the richest source of nitrogen on a mass percentage basis because it has 82.35% of nitrogen by mass.

Explanation:

Percentage of element in compound :

=\frac{\text{number of atoms}\times text{Atomic mass}}{\text{molar mas of compound}}\times 100

(a) Urea, (NH_2)_2CO

Molar mass of urea = 60 g/mol

Atomic mass of nitrogen = 14 g/mol

Number of nitrogen atoms = 2

N\%=\frac{2\times 14 g/mol}{60 g/mol}\times 100=46.67\%

(b) Ammonium nitrate, NH_4NO_3

Molar mass of ammonium nitrate = 80 g/mol

Atomic mass of nitrogen = 14 g/mol

Number of nitrogen atoms = 2

N\%=\frac{2\times 14 g/mol}{80 g/mol}\times 100=35.00\%

(c) Nitric oxide, NO

Molar mass of nitric oxide  = 30 g/mol

Atomic mass of nitrogen = 14 g/mol

Number of nitrogen atoms = 1

N\%=\frac{1\times 14 g/mol}{30 g/mol}\times 100=46.67\%

(d) Ammonia, NH_3

Molar mass of ammona = 17 g/mol

Atomic mass of nitrogen = 14 g/mol

Number of nitrogen atoms = 1

N\%=\frac{1\times 14 g/mol}{17 g/mol}\times 100=82.35\%​

Ammonia is the richest source of nitrogen on a mass percentage basis because it has 82.35% of nitrogen by mass.

4 0
3 years ago
Can you pls tell me the word equations for all these equations​
Leokris [45]

Answer:

Below

Explanation:

Balanced form;

2C_6H_6 +15O_2 -> 12CO_2+6H_2O\\\\ Ca_3(PO_4)_2 +8C -> Ca_3P_2 +8CO\\\\2HNO_2+O_2 -> 2HNO_3\\\\Ca(OH)_2 + CO_2 -> CaC0_3+H_2O\\\\2K +Br_2 ->2KBr\\\\2NaOH+FeSO_4 -. Na_2SO_4 +Fe(OH)_2

1.Benzene + Dioxygen = Carbon Dioxide + Water

2.Tricalcium phosphate +Carbon = Calcium phosphide + carbon monoxide

3.Nitrous acid react with oxygen to produce nitric acid.

4.This means that the carbon dioxide and limewater react to produce calcium carbonate and water.

5.Potassium react with bromine to produce potassium bromide

6. An aqueous solution of ferrous sulphate reacts with aqueous solution of sodium hydroxide to form a precipitate of ferrous hydroxide and sodium sulphate remains in the solution.

5 0
3 years ago
In the reaction
ivolga24 [154]
Water is the BL base if it accepted a proton from NH4.
Can I get brainliest please?
7 0
2 years ago
3. Analizando la siguiente reacción química de formación del agua:
Leya [2.2K]

Answer:

3. Analizando la siguiente reacción química de formación del agua:

2 H2 (g) + O2 (g)  2 H2O (l)

Si se hacen reaccionar 10 g de hidrógeno con 10 g de oxígeno:

a) Plantee las razones molares de dicha ecuación

b) Determine si se consumen la totalidad de dichos reactivos. Demuéstrelo con los cálculos estequiométricos correspondientes.

5 0
3 years ago
The reaction between nitrogen dioxide and carbon monoxide is NO2(g)+CO(g)→NO(g)+CO2(g)NO2(g)+CO(g)→NO(g)+CO2(g) The rate constan
Alex17521 [72]

Answer : The rate constant at 525 K is, 0.0606M^{-1}s^{-1}

Explanation :

According to the Arrhenius equation,

K=A\times e^{\frac{-Ea}{RT}}

or,

\log (\frac{K_2}{K_1})=\frac{Ea}{2.303\times R}[\frac{1}{T_1}-\frac{1}{T_2}]

where,

K_1 = rate constant at 701K = 2.57M^{-1}s^{-1}

K_2 = rate constant at 525K = ?

Ea = activation energy for the reaction = 1.5\times 10^2kJ/mol=1.5\times 10^5J/mol

R = gas constant = 8.314 J/mole.K

T_1 = initial temperature = 701 K

T_2 = final temperature = 525 K

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

\log (\frac{K_2}{2.57M^{-1}s^{-1}})=\frac{1.5\times 10^5J/mol}{2.303\times 8.314J/mole.K}[\frac{1}{701K}-\frac{1}{525K}]

K_2=0.0606M^{-1}s^{-1}

Therefore, the rate constant at 525 K is, 0.0606M^{-1}s^{-1}

8 0
3 years ago
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