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3 years ago

The goal of this lesson is to answer the lesson

Chemistry

2 answers:

OverLord2011 [107]3 years ago

5 0

Answer:

The half life for radioactive can be calculated as:

N /N0 = (1 /2) ^ n

n = T /T half

According to question there are n number of half life are present which would result in remaining amount of element as n.

Explanation:

Sorry if wrong

Scilla [17]3 years ago

4 0

Answer:

1. atom

2. 0.5n

Explanation:

Because half of the atom's nuclei will decay during each cycle.

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Which cells produce photosynthesis

AnnZ [28]

Hey there,

Answer:

Photosynthetic cell

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3 years ago

Given the following at 25C calculate delta Hf for HCN (g) at 25C. 2NH3 (g) +3O2 (g) + 2CH4 (g) ---> 2HCN (g) + 6H2O (g) delta

AysviL [449]

Answer: The $\Delta H_f$ for HCN (g) in the reaction is 135.1 kJ/mol.

Explanation:

Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles. The equation used to calculate enthalpy change is of a reaction is:

$\Delta H_{rxn}=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]$

For the given chemical reaction:

$2NH_3(g)+3O_2(g)+2CH_4(g)\rightarrow 2HCN(g)+6H_2O(g)$

The equation for the enthalpy change of the above reaction is:

$\Delta H_{rxn}=[(2\times \Delta H_f_{(HCN)})+(6\times \Delta H_f_{(H_2O)})]-[(2\times \Delta H_f_{(NH_3)})+(3\times \Delta H_f_{(O_2)})+(2\times \Delta H_f_{(CH_4)})]$

We are given:

$\Delta H_f_{(H_2O)}=-241.8kJ/mol\\\Delta H_f_{(NH_3)}=-80.3kJ/mol\\\Delta H_f_{(CH_4)}=-74.6kJ/mol\\\Delta H_f_{(O_2)}=0kJ/mol\\\Delta H_{rxn}=-870.8kJ$

Putting values in above equation, we get:

$-870.8=[(2\times \Delta H_f_{(HCN)})+(6\times (-241.8))]-[(2\times (-80.3))+(3\times (0))+(2\times (-74.6))]\\\\\Delta H_f_{(HCN)}=135.1kJ$

Hence, the $\Delta H_f$ for HCN (g) in the reaction is 135.1 kJ/mol.

8 0

3 years ago

I’ll really appreciate it if you help me out on this one .

Westkost [7]

1.
-Water levels are dangerously high for wildlife and humans.
-Animals seem to be lost, like the cow and the sheep especially.

2.
-There are not many trees near the water, meaning less areas for wildlife to live.
-There is not much wildlife in general.

Inferences
1. The wildlife shown will move relocate and adapt to another area.
2. Industry — emissions are visible in top left— will continue to hurt the environment. CO2 emissions will increase.

Good luck!

5 0

3 years ago

how many grams of oxygen gas are needed to produce 10.0 grams of carbon dioxide according to the balanced equation of CH4

Alinara [238K]

Molar mass of :

O2 = 16 * 2 = 32 g/mol

CO2 = 12 + 16 * 2 = 44 g/mol

Balanced chemical equation :

1 CH4 + 2 O2 = 1 CO2 + 2 H2O
↓ ↓
2 moles 1 mole

2* 32 g O2 ----------> 1* 44 g CO2
x g O2 ------------> 10.0 g CO2

44 x = 2 * 32*10.0

44 x = 640

$x = \frac{640}{44}$

$x = 14.54 g$ of O2

7 0

3 years ago

What is the relationship between a mole and Avogadro number

docker41 [41]

A mole contains Avogadro’s number of particles of a substance.

4 0

4 years ago

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