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4 years ago

Which of these is an indicator that a chemical reaction has occurred?

1 answer:

7 0

One of the common indicators that a chemical reaction has occurred is if the react ants reacting produce a precipitate that is insoluble within the solution and forms.

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How many liters of carbon dioxide will be produced when 89.5 L of ethane are burned? (One mole of any gas occupies 22.4 L under

yan [13]

Answer:

179 L of CO2

Explanation:

Given the equation of the reaction;

C2H6(g) + 7/2 O2(g) -------> 2CO2(g) + 3H2O(g)

Now 1 mole of ethane yields 2 moles of CO2 from the balanced reaction equation

1 mole of a gas occupies 22.4 L volume so,

22.4 L of ethane yields 44.8 L of CO2

89.5 L of ethane yields 89.5 * 44.8/22.4 = 179 L of CO2

4 0

3 years ago

Please somebody give me the answers

RSB [31]

Answer:

1. 9.4 grams of methane produce 25.85 grams of CO2

2.Grams of water produced = 11.81 grams

3.Mass of Methane produced by 10.1 gram of O2 = 2.52 grams

4.Amount of methane consumed = 46.9 grams

5. Grams of Co2 produced = 8.32 grams

Explanation:

Molar masses :

Methane = CH4 = mass of C + 4x (mass of H)

CH4 = 12 +4(1) = 16 grams

1 mole of CH4 = 16 gram

Oxygen O2 = 2 x (mass of O) = 2x(16) = 32 gram (1 mole of O2 =32 gram)

Carbon Dioxide =CO2 = mass of C + 2(mass of O)

= 12 + 2(16)

= 44 grams (1 mole of CO2 = 44 gram )

Water = H2O = 18 grams ( 1 mole of H2O = 18 gram)

1 mole of each molecule is equal to their molar masses

The balanced equation is :

$1CH_{4}(g)+2O_{2}\rightarrow 1CO_{2}+2H_{2}O(l)$

According to Stoichiometry :

1 mole of CH4 = 2 Mole of O2 = 1 mole of CO2 = 2 mole of H2O

1. From the equation ,

1 mole of methane produce =1 mole of CO2

16 gram of methane = 44 gram of CO2

1 gram of methane =

$\frac{44}{16}$ gram of CO2

9.4 gram of CH4 =

$\frac{44}{16}\times 9.4$ gram of CO2

= 25 .85 gram of CO2

2 mole of O2 produces = 2 mole of H2O(water)

1 mole of O2 produces = 1 mole of H2O

32 gram of O2 = 18 gram of water

1 gram of O2 =

$\frac{18}{32}$

21 gram of O2 =

$\frac{18}{32}\times 21$

11.81 gram of water

3. 1 mole of CH4 = 2 mole of O2

16 gram of CH4 = 2(32) = 64 grams of O2

64 gram of O2 needs = 16 grams of CH4

1 gram of O2 needs =

$\frac{16}{64}$

10.1 gram of O =

$\frac{16}{64}\times 10.1$ of CH4

= 2.52 gram

1 mole of CO2 is produced from = 1 mole of CH4

44 gram of CO2 is produced from 16 gram of CH4

1 gram CO2 =

$\frac{16}{44}$ gram of CH4

129 gram of CO2 =

$\frac{16}{44}\times 129$ gram of CH4

= 46.90 grams

2 mole of O2 produce = 1 mole of CO2

2x 32 gram of O2 = 44 gram of CO2

1 gram of O2 =

$\frac{44}{64}$ of CO2

12.1 gram of O2 produce=

$\frac{44}{64}\times 12.1$ of CO2

= 8.318 gram

Note : Write the quantity give on left side of "="

write the substance asked on right side of "="

8 0

3 years ago

Covert to scientific notation.

gtnhenbr [62]

Answer:

19) 3.6920 × 10⁻⁵

20) 4.059× 10²

21) 2.46810121416 × 10³

22) 1.0000× 10⁻³

Explanation:

Scientific notation is the way to express the large value in short form.

The number in scientific notation have two parts.

The digits (decimal point will place after first digit)

× 10 ( the power which put the decimal point where it should be)

For example:

0.000036920

In scientific notation = 3.6920 × 10⁻⁵

405.9

In scientific notation = 4.059× 10²

2468.10121416

In scientific notation = 2.46810121416 × 10³

0.0010000

In scientific notation = 1.0000× 10⁻³

8 0

3 years ago

Record your findings about sound and light waves for each of the following.

Troyanec [42]

Answer:

Sound waves travelling through the air: Sound waves travelling through air are just like longitudinal waves lacking compressions and rarefactions. The speed of sound waves in air is approximately 332 metres per second.

Light waves travelling through air: Light waves travel in air at a much faster rate than sound waves. Light waves can travel with a speed of 300 000 kilometres per second through air.

Sound waves traveling through metal: Sound waves travel about 17 times faster in metal as compared to air. The sound waves travel with an approximate speed of 5,960 meters per second in metals.

Light waves travelling through metal: The speed of light waves in a metal medium is usually at a net speed which is less than 3.00 x 108 m/s.

Light travels faster than sound waves because light waves are not pressure waves like the sound waves. They also do not require a medium as the sound waves.

7 0

3 years ago

Small quantities of hydrogen gas can be prepared in the laboratory by the addition of aqueous hydrochloric acid to metallic zinc

Alexxx [7]

Explanation:

The given data is as follows.

Pressure of moist hydrogen gas = 1.018 atm

Pressure of water vapor = $32 torr \times \frac{1 atm}{760 torr}$