1.
What entities are usually on the left hand side of a chemical equation?
Correct Answer
B. Reactant
Explanation
In a chemical equation, the entities that are usually on the left hand side are called reactants. Reactants are the substances that undergo a chemical reaction and are consumed during the process. They are written on the left side of the equation, while the products (the substances formed as a result of the reaction) are written on the right side. Therefore, the correct answer is Reactant.
2.
What entities are usually on the right hand side of a chemical equation?
Correct Answer
A. Product
Explanation
In a chemical equation, the entities that are usually on the right hand side are called the products. These are the substances that are formed as a result of the chemical reaction. Reactants, on the other hand, are the substances that are present at the beginning of the reaction and are typically found on the left hand side of the equation. Ionic and atomic are not specific entities that are typically found on either side of a chemical equation, so they are not the correct answer.
3.
What are coefficients next to the symbols and formulae of entities known as? The Absolute values of ______
Correct Answer
A. Stoichiometric numbers Â
Explanation
The coefficients next to the symbols and formulae of entities are known as stoichiometric numbers. These numbers represent the relative amounts of each substance involved in a chemical reaction. They indicate the ratio in which the reactants combine and the products are formed. Stoichiometric numbers are essential in balancing chemical equations and determining the quantitative relationships between reactants and products.
4.
Who diagrammed the first chemical equation?
Correct Answer
A. Jean Beguin
Explanation
Jean Beguin is credited with diagramming the first chemical equation. He was a French chemist who lived during the 16th century. Beguin's work in chemistry included the study of chemical reactions and the development of chemical symbols and notation. He is known for his book "Tyrocinium Chymicum," which was published in 1615 and included the first recorded chemical equation. Beguin's contribution to the field of chemistry helped establish a standardized way of representing chemical reactions, which is still used today.
5.
What year was the first chemical equation diagrammed?
Correct Answer
C. 1615
Explanation
In 1615, the first chemical equation was diagrammed. This suggests that prior to this year, chemical reactions were not represented using equations. The diagramming of the chemical equation marked a significant milestone in the history of chemistry, as it allowed scientists to visually represent the reactants and products involved in a chemical reaction. This development laid the foundation for further advancements in the field of chemistry and paved the way for the modern understanding of chemical reactions.
6.
What are the reactants in a chemical equation?
Correct Answer
A. The starting substance Â
Explanation
The reactants in a chemical equation refer to the starting substances that undergo a chemical reaction to form new substances. In other words, they are the substances present before the reaction takes place and are written on the left side of the equation. These reactants are consumed during the reaction and are transformed into the formed substances, which are written on the right side of the equation. Ions and atoms are components of both the reactants and the formed substances, but they are not the reactants themselves.
7.
What are the products in a chemical equation?
Correct Answer
B. The formed substance
Explanation
The products in a chemical equation refer to the substances that are formed as a result of a chemical reaction. These substances are produced from the starting substances, also known as reactants. In a balanced chemical equation, the reactants are written on the left side of the equation and the products are written on the right side. The formed substance is the correct answer as it accurately represents the substances that are generated during a chemical reaction.
8.
Which of these equations denote the reaction of hydrochloric acid with sodium?
Correct Answer
A. 2 HCl + 2 Na → 2 NaCl + H2
Explanation
The correct answer is 2 HCl + 2 Na → 2 NaCl + H2. This equation represents the reaction of hydrochloric acid (HCl) with sodium (Na) to form sodium chloride (NaCl) and hydrogen gas (H2). The balanced equation shows that for every 2 moles of hydrochloric acid and 2 moles of sodium, 2 moles of sodium chloride and 1 mole of hydrogen gas are produced.
9.
Which of these represents sodium?
Correct Answer
A. Na
Explanation
The correct answer is Na. Sodium is represented by the chemical symbol Na on the periodic table.
10.
When stating physical state, what denotes a solid?
Correct Answer
A. S
Explanation
In the context of stating physical state, the letter "S" denotes a solid.