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3 years ago

ASAP HELP WILL MARK BRAINLIEST FOR BEST ANSWER. MUST ANSWER WITHIN 6 MIN!!!

Chemistry

2 answers:

Vesnalui [34]3 years ago

7 0

Answer:

3 molecules

Explanation: i got it right on the test, also because the 2 other ones are compounds because they have hyrdogen and oxygen attached and molecules just have particles of one element attached

Dafna1 [17]3 years ago

3 0

Answer:

3 molecules

Explanation:

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The following chemical reaction occurs in a basic solution.

Dafna1 [17]

Answer:

6 moles of electrons

Explanation:

Let us consider the species NO3− and ClO−. The NO3− is oxidized to NO the oxidation number of nitrogen is decreased from +5 to +2.

The oxidation number of chlorine is increased from +1 to +3. This implies that six electrons were transferred in the balanced reaction equation shown in the question. Hence the answer.

3 0

3 years ago

Check all items common to bases. minerals metal gas H+ OH- nitrogen

Darya [45]

OH- is common to bases.

Explanation:

The base is a is an ionic compounds which when placed in aqueous solution dissociates in to a cation and an anion OH-.

The presence of OH- in the solution shows that the solution is basic or alkaline.

From Bronsted and Lowry concept base is a molecule that accepts a proton for example in NaOH, Na is a proton donor and OH is the proton acceptor.

A base accepts hydrogen ion and the concentration of OH is always higher in base.

There is a presence of conjugate acid and conjugate base in the Bronsted and Lowry acid and base.

Conjugate acid is one which is formed when a base gained a proton.

Conjugate base is one which is formed when an acid looses a proton.

And from the Arrhenius base Theory, the base is one that dissociates in to water as OH-.

8 0

3 years ago

A method used by the U.S. Environmental Protection Agency (EPA) for determining the concentration of ozone in air is to pass the

baherus [9]

Answer: 1. $9.08\times 10^{-6}$ moles

2. 90 mg

Explanation:

$O_3(g)+2NaI(aq)+H_2O(l) \rightarrow O_2(g)+I_2(s)+2NaOH(aq)$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus $4.54 \times 10^{-6}$ moles of ozone is removed by = $\frac{2}{1}\times 4.54 \times 10^{-6}=9.08\times 10^{-6}$ moles of sodium iodide.

Thus $9.08\times 10^{-6}$ moles of sodium iodide are needed to remove $4.54\times 10^{-6}$ moles of $O_3$

2. $\text{Number of moles of ozone}=\frac{0.01331g}{48g/mol}=0.0003moles$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus 0.0003 moles of ozone is removed by = $\frac{2}{1}\times 0.0003=0.0006$ moles of sodium iodide.

Mass of sodium iodide= $moles\times {\text {molar mass}}=0.0006\times 150g/mol=0.09g=90mg$ (1g=1000mg)

Thus 90 mg of sodium iodide are needed to remove 13.31 mg of $O_3$ .

3 0

3 years ago

Why are hydrogen bonds so essential to the structure of dna?

Lelu [443]

Hydrogen bonds hold the paired nitrogenous bases together. Because hydrogen bonds are weak bonds, the two strands of DNA are easily separated a characteristic that is important to DNA's function.Hydrogen bonds form between adenine and thymine and between cytosine and guanine.

4 0

3 years ago

A flask contains an equal mixture of oxygen and argon. Which of the following statements is true about the effusion of the gases

frozen [14]

Given that the pressure, temperature and area of effusion is constant, the rate of effusion is inversely proportional to the square root of the molecular mass of the gas.
Mr Oxygen = 32
Mr Argon = 40
Effusion Oxygen = 1/√32
Effusion Argon = 1/√40
Effusion Oxygen / Effusion Argon = √(40) / √(32)
=√(40/32) = √(5/4) = 1.19
Thus, Oxygen will effuse 1.19 times faster than Argon. The second option is correct.

8 0

3 years ago