Answer:
air is a group of different gases and gas is loose bound atoms of an element
Explanation:
Answer:
A charge of -3
Explanation:
If you look on a periodic table you will find that phosphorus is 3 elements away from the nearest noble gas argon. This means that phosphorus would prefer a charge of -3!
Answer:
0.56 M
Explanation:
Step 1: Given data
- Rate constant (k): 0.035 s⁻¹
- Initial concentration of the reactant ([A]₀): 1.5 M
Step 2: Calculate the amount of reactant ([A]) after 28 seconds
For a first-order kinetics, we will use the following expression.
ln [A] = ln [A]₀ - k × t
ln [A] = ln 1.5 - 0.035 s⁻¹ × 28 s
[A] = 0.56 M
The answer is (3) 3. The calculation rule of significant figures is when multiplication and division, the significant figures of result is equal to the least of the numbers involved. The significant figure of 2.70 and 80.01 is 3 and 4.
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.