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2 years ago

What is the atomic mass of heilum

Chemistry

1 answer:

blondinia [14]2 years ago

5 0

Helium's atomic mass is 4 because atomic number is 2.

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Calculate the ratio of H+ ions to OH– ions at a pH = 8. Find the concentration of H+ ions to OH– ions listed in Table B of your

goldenfox [79]

Answer:

0.00000001 mol/L

0.000001 mol/L

0.01: 1 OR 1: 100

Explanation:

Just did it

8 1

2 years ago

Read 2 more answers

Which element is considered the foundation for making organic compounds

Rasek [7]

Answer: Carbon

Explanation: Organic compounds are those made by carbon atoms that link to other carbon or elements such as nitrogen, hydrogen or oxygen with covalent bonds.

The presence of these compounds were associated with living things, because most of them are produced by plants or animals. However nowdays substances like polymers and other synthetically made molecules can also be considered as organic since they are made of carbon.

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2 years ago

Air is classified as a mixture. What statement must be true about air? (4D)

Taya2010 [7]

Answer:

C.)Air is made up of atoms of one elements

6 0

2 years ago

For the oxidation of ammonia

OverLord2011 [107]

The answer is 0.405 M/s

- (1/3) d[O2]/dt = 1/2 d[N2]/dt

- d[O2]/dt = 3/2 d[N2]/dt

- d[O2]/dt = 3/2 × 0.27

- d[O2]/dt = 0.405 mol L^(-1) s^(-1)

5 0

2 years ago

Cars run on gasoline, where octane (C8H18) is the principle component. This combustion reaction is responsible for generating en

Bezzdna [24]

Answer:

10.19 g CO₂

4.69 g H₂O

Explanation:

The combustion reaction of Octane is:

C₈H₁₈ → 8CO₂ + 9H₂O

To calculate the mass of CO₂ and H₂O produced, we need to know the mass of octane combusted.

We calculate the mass of Octane from the given volume and density, using the following conversion factors:

1 gallon = 3.785 L

1 L = 1000 mL

Now we convert 1.24 gallons to mL:

1.24 gallon * $\frac{3.785L}{1gallon} *\frac{1000mL}{1L} =$ 4693.4 mL

We calculate the mass of Octane:

4693.4 mL * 0.703 g/mL = 3.30 g Octane

Now we use the stoichiometric ratios and molecular weights to calculate the mass of CO₂ and H₂O:

CO₂ ⇒ 3.30 g Octane ÷ 114g/mol * $\frac{8molCO_{2}}{1molOctane}$ * 44 g/mol = 10.19 g CO₂

H₂O ⇒ 3.30 g Octane ÷ 114g/mol * $\frac{9molH_{2}O}{1molOctane}$ * 18 g/mol = 4.69 g H₂O

7 0

3 years ago