Answer:
Option A, The Rutherford experiment proved the Thomson "plum-pudding" model of the atom to be essentially correct.
Explanation:
Thomson's plum pudding model:
Plum pudding model was proposed by J.J Thomson. In Thomson's model, atoms are proposed as sea of positively charge in which electrons are distributed through out.
Result of Rutherford experiment:
As per Rutherford's experiment:
Most of the space inside the atom is empty.
Positively charge of the atom are concentrated in the centre of the atom known as nucleus.
Electrons are present outside the nucleus and revolve around it.
As it is clear that, result of Rutherford experiment did not supported the Thomson model.
<u>Answer:</u> The balanced chemical equation for the reaction of nitric acid and calcium hydroxide is written below.
<u>Explanation:</u>
A balanced chemical equation is defined as the equation in which total number of individual atoms on the reactant side is equal to the total number of individual atoms on product side.
The balanced chemical equation for the reaction of nitric acid and calcium hydroxide follows:
By Stoichiometry of the reaction:
2 moles of nitric acid reacts with 1 mole of calcium hydroxide to produce 1 mole of calcium nitrate and 2 moles of water molecule.
Hence, the balanced chemical equation for the reaction of nitric acid and calcium hydroxide is written below.
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.
