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3 years ago

Which of the following statements is true?

Chemistry

2 answers:

Darya [45]3 years ago

7 0

B. The nucleus of an atom contains protons and neutrons.

jeka57 [31]3 years ago

3 0

B. The nucleus of an atom contains protons and neutrons.

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The following reactions have the indicated equilibrium constants at a particular temperature: N2(g) + O2(g) ⇌ 2NO(g) Kc = 4.3 ×

Anuta_ua [19.1K]

Answer:

$Kc=~1.49x10^3^4}$

Explanation:

We have the reactions:

A: $N_2_(_g_) + O_2_(_g_) 2NO_(_g_)~~~~~~Kc = 4.3x10^-^2^5$

B: $2NO_(_g_)+~O_2_(_g_)~2NO_2_(_g_)~~~Kc = 6.4x10^9$

Our target reaction is:

$4NO_(_g_) N_2_(_g_) + 2NO_2_(_g_)$

We have $NO_(_g_)$ as a reactive in the target reaction and $NO_(_g_)$ is present in A reaction but in the products side. So we have to flip reaction A.

A: $2NO_(_g_) N_2_(_g_) + O_2_(_g_) ~Kc =\frac{1}{4.3x10^-^2^5}$

Then if we add reactions A and B we can obtain the target reaction, so:

A: $2NO_(_g_) N_2_(_g_) + O_2_(_g_) ~Kc =\frac{1}{4.3x10^-^2^5}$

B: $2NO_(_g_)+~O_2_(_g_)~2NO_2_(_g_)~Kc=6.4x10^9$

For the final Kc value, we have to keep in mind that when we have to add chemical reactions the total Kc value would be the multiplication of the Kc values in the previous reactions.

$4NO_(_g_) N_2_(_g_) + 2NO_2_(_g_)~~~Kc=\frac{6.4x10^9}{4.3x10^-^2^5}$

$Kc=~1.49x10^+^3^4}$

3 0

2 years ago

Significant digits are the number of digits that reflect the precision of a measurement or number.

Delvig [45]

Answer:

True

Explanation:

Significant digits are numbers that helps to present the precision of measurements calculations.

Numbers that do not contribute to the precision of a reading should not be counted as significant.

There are rules of assigning significant numbers:

Leading or trailing zeros are insignificant and should only be counted as a place holder.
All non-zero digits are significant
Zeroes between non-zero digits are significant.
Leading zeros in a decimal are significant before the number.
All the numbers in a scientific notation are significant.

5 0

3 years ago

Which planet listed below will take the longest amount of time to orbit the sun?

Tema [17]

Answer:

Neptune takes the longest to orbit the sun because of it's distance away from the Sun.

Explanation:

5 0

2 years ago

3. What role did the government play in either supporting or suppressing African Americans'/Blacks'

9966 [12]

Slavery played a big role in this. the confederacy allowed slavery while the union was oppose to it.

4 0

2 years ago

Examine the molecular structure of this lipid. What type of lipid is this?

artcher [175]

The correct answer is Phospholipid

3 0

3 years ago