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4 years ago

I need help with the one with the pen on it

Chemistry

2 answers:

Setler [38]4 years ago

5 0

<span>The human body is organized at different levels, starting with the cell. Cells are organized into tissues, and tissues form organs. Organs are organized into organ systems such as the skeletal and muscular systems.</span>

Pavel [41]4 years ago

5 0

Q: What is the job of your heart?
A: Your heart is sort of like a pump, or two pumps in one. The right side of your heart receives blood from the body and pumps it to the lungs.

Answered this just to help out. I seen that your question was answered.

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7. NH2CO2NH4(s) when heated to 450 K undergoes the following reaction to produce a system which reaches equilibrium: NH2CO2NH4(s

Taya2010 [7]

Answer:

Value of equilibrium constant is 0.0888

Explanation:

Both $NH_{3}$ and $CO_{2}$ are gaseous. Hence equilibrium constant depends upon partial pressures of $NH_{3}$ and $CO_{2}$ .

Initially no $NH_{3}$ and $CO_{2}$ were present.

Hence mole fraction of $NH_{3}$ and $CO_{2}$ at equilibrium can be calculated from coefficient of $NH_{3}$ and $CO_{2}$ in balanced equation.

Mole fraction of $NH_{3}$ = (number of moles of $NH_{3}$ )/(total number of moles of $NH_{3}$ and $CO_{2}$ ) = $\frac{2moles}{(2+1)moles}=\frac{2}{3}$

Mole fraction of $CO_{2}$ = (number of moles of $CO_{2}$ )/(total number of moles of $NH_{3}$ and $CO_{2}$ ) = $\frac{1moles}{(2+1)moles}=\frac{1}{3}$

Let's assume both $CO_{2}$ and $NH_{3}$ behaves ideally.

Therefore partial pressure of $NH_{3}$ , $P_{NH_{3}}= x_{NH_{3}}.P_{total}$ and P_{CO_{2}}= x_{CO_{2}}.P_{total}

Where x represents mole fraction

So, $P_{NH_{3}}=\frac{2}{3}\times 0.843atm=0.562atm$

$P_{CO_{2}}=\frac{1}{3}\times 0.843atm=0.281atm$

So, $K_{p}=P_{NH_{3}}^{2}.P_{CO_{2}}=(0.562)^{2}\times 0.281=0.0888$

4 0

3 years ago

What is one beneift of using scientific notation instead of regular notation

kotykmax [81]

Answer:

its shorter than a regular one

Explanation:

the only reason is simply because it is shorter

8 0

3 years ago

Which element consists of positive ions immersed in a "sea" of mobile electronsa) sulfur

Margarita [4]

Hello
Sulfur is the answer

5 0

3 years ago

Under certain conditions the rate of this reaction is zero order in dinitrogen monoxide with a rate constant of 0.0067·Ms−1: 2N2

choli [55]

Answer:

5.6 seconds

Explanation:

The reaction follows a zero-order in dinitrogen monoxide

Rate = k[N20]^0 = change in concentration/time

[N20]^0 = 1

Time = change in concentration of N2O/k

Initial number of moles of N2O = 300 mmol = 300/1000 = 0.3 mol

Initial concentration = moles/volume = 0.3/4 = 0.075

Number of moles after t seconds = 150 mmol = 150/1000 = 0.15 mol

Concentration after t seconds = 0.15/4 = 0.0375 M

Change in concentration of N2O = 0.075 - 0.0375 = 0.0375 M

k = 0.0067 M/s

Time = 0.0375/0.0067 = 5.6 s

4 0

3 years ago

An unknown compound contains 38.7 % calcium, 19.9 % phosphorus and 41.2 % oxygen. what is the empirical formula of this compound

Softa [21]

Answer: Ca3(PO4)2

Explanation:

We assume that the sample is 100.0 g.

The sample contains 38.7 g of Ca, 19.9 g of P, and 41.2 g of O as the proportions show.

Then we can calculate the number of moles of each component (n = m/atomic mass).

The number of moles of Ca = 38.7/40.078 = 0.96 mol.

The number of moles of P = 19.9/30.97 = 0.64 mol.

The number of moles of O = 41.2/15.99 = 2.75 mol.

Now, we can get the molar ratios of different components (Ca, P, and O) in the sample by dividing the number of moles of each component by the lower number of moles, that we should divide the number of moles by (0.64).

Ca: P: O = (0.96/0.64) : (0.64/0.64) : (2.75/0.64) = 1.5 : 1 : 4.

To avoid the fraction of the ratios, we can multiply all ratios by 2.0.

Now, the ratio of Ca : P : O will be 3 : 2 : 8.

That main the empirical formula of the compound is Ca3P2O8 which can be expressed as calcium phosphate (Ca3(PO4)2).

8 0

3 years ago