WILL GIVE BRAINLIEST. How does Earth's distance from the sun make it advantageous for supporting life?

Properties of substances can be classified as physical or chemical properties. Which statements describe chemical properties? (C

Tamiku [17]

The correct answers are options C, that is, silver tarnishes and becomes black when exposed to oxygen, and option E, that is, diesel fuel burns when it is heated.

Chemical changes refer to the modifications in which the chemistry at molecular level is modified as the initial substance gets transformed into a new and different final substance. This change occurs with the dissociation of old bond and production of new bonds respectively.

Silver gets tarnished and becomes black when exposed to oxygen. This refers to a chemical change as silver a white and lustrous substance gets transformed into a tarnish black final substance. However, silver does not easily react with oxygen at usual circumstances. It easily reacts with sulfur comprising components in the air and generates black compound as Ag₂S.

Burning of diesel fuel when it is heated. Diesel refers to a mixture of hydrocarbons varying approximately from C₁₀H₂₀ to C₁₅H₂₈. When these hydrocarbons get burnt they generate novel substances, that is, carbon dioxide and water. Hence, it is also a chemical reaction.

5 0

4 years ago

When iron nail is ground into powder, it’s mass

Stolb23 [73]

Answer:

(a) The mass of an object remains the same always. It is independent of its location. In this case, an iron nail is ground into powder.

Explanation:

please mark this answer as brainliest

5 0

4 years ago

The reaction of solid aluminum with hydrochloric acid is used to make hydrogen gas in a laboratory experiment. The reaction is 2

Gemiola [76]

Answer:

0.003088 moles of hydrogen gas were formed .

Explanation:

Pressure at which hydrogen gas is collected at 20°C = 768.0 Torr

Vapor pressure of water at 20°C = 17.5 Torr

Total pressure = Vapor pressure of water + Partial pressure of hydrogen gas

Partial pressure of hydrogen gas:

Total pressure - Vapor pressure of water

= 768.0 Torr - 17.5 Torr = 750.5 Torr = 0.987 atm

(1 Torr = 0.001315 atm)

Pressure of hydrogen gas =P = 0.986 atm

Temperature at which gas was collected ,T= 20°C = 293.15 K

Volume of the gas ,V= 75.3 mL = 0.0753 L

Moles of hydrogen gas = n

PV=nRT (An ideal gas equation)

$n=\frac{PV}{RT}=\frac{0.987 atm\times 0.0753 L}{0.0821 atm L/mol K\times 293.15 K}=0.003088 mol$

0.003088 moles of hydrogen gas were formed .

7 0

4 years ago

7. How many moles are in 56.0 grams of Silicon

agasfer [191]

Answer:

1.9939114489683198 moles

Explanation:

3 0

3 years ago

Chromatography Portfolio

ki77a [65]

5. It was evident that the marker ink is a mixture because when it was subjected to chromatography process the constituent materials which made up the marker ink got separated and appear as different bands on the chromatography paper.
6. YES, the constituents of the marker have different travelling speed, so some travel slowly while others are fast. Their travelling rates depend on the mobile phases that are used during the chromatography process.
The constituents of the marker has different travelling speed because each one of them react differently with the mobile solvent that is used. Those constituents that have high affinity for the solvent used will travel faster that those that did not.
7. The mixture travel faster in alcohol that in water. This is because the ink dissolves more in the rubbing alcohol and has higher affinity for rubbing alcohol compare with water.
8. I can improve on my RF measurement by making sure that I read to the millimeter marks when taking my readings with ruler and by making sure that I record my value to four significant figures.

5 0

4 years ago