Chapter 7 Quiz - Chemistry

Chemicals that result from a chemical reaction are called products. In a chemical reaction, reactants undergo a transformation and form new substances known as products. These products can have different physical and chemical properties compared to the reactants. The formation of products is a fundamental concept in chemistry and is crucial in understanding the changes that occur during chemical reactions.

Reactants are the chemicals at the beginning of a reaction. They are the starting materials that undergo a chemical change to form products. In a chemical reaction, reactants are transformed into new substances through the breaking and forming of chemical bonds. Therefore, reactants play a crucial role in initiating and driving the reaction forward.

The term for the number in front of a chemical formula in a chemical equation is called a coefficient. It represents the number of moles or molecules of a substance involved in the reaction. Coefficients are used to balance chemical equations by ensuring that the number of atoms on both sides of the equation is equal. Subscripts, on the other hand, are used to indicate the number of atoms of a specific element within a molecule, while superscripts are used for indicating the charge of an ion. Variables are symbols used to represent unknown quantities in mathematical equations.

The symbol "aq" is used to represent the term "aqueous" in chemistry. Aqueous refers to a solution in which water is the solvent. It is commonly used to indicate that a substance is dissolved in water. Therefore, the correct answer is "aqueous."

Silver nitrate is soluble because it dissolves in water to form a solution. This is due to the ionic nature of silver nitrate, where the silver ion (Ag+) and nitrate ion (NO3-) dissociate in water. The water molecules surround and separate the ions, allowing them to move freely in the solution. Therefore, silver nitrate is considered soluble in water.

A chemical equation is used to represent a chemical reaction. It shows the reactants on the left side and the products on the right side, separated by an arrow. The chemical equation provides information about the substances involved in the reaction and their respective quantities. It allows scientists to understand the stoichiometry of the reaction, meaning the ratios in which the reactants combine and the products are formed. Therefore, a chemical equation is the most appropriate representation for a chemical reaction.

Lithium hydroxide is soluble because it dissolves in water to form lithium ions (Li+) and hydroxide ions (OH-). This compound is classified as a strong base, meaning it readily dissociates in water. Solubility is a property that describes the ability of a substance to dissolve in a solvent, and in the case of lithium hydroxide, it readily dissolves in water, making it soluble.

The given sequence follows a pattern where each row consists of alternating numbers. The first row has all 1s, the second row alternates between 2 and 1, the third row alternates between 1 and 2, and the fourth row alternates between 2 and 1. Thus, the answer is 1, 1, 1, 1.

BaSO4, also known as barium sulfate, is generally considered insoluble in water. It has a very low solubility, meaning that only a small amount of BaSO4 can dissolve in water. This is due to the strong ionic bonds between the barium and sulfate ions in the compound. As a result, BaSO4 is often used as a contrast agent in medical imaging because it does not dissolve easily in the body. Therefore, the correct answer is False.

Calcium carbonate is insoluble in water. This means that it does not readily dissolve or mix with water. Instead, it forms a solid precipitate when calcium ions and carbonate ions come together. This can be observed in nature, such as in the formation of limestone and marble. Additionally, calcium carbonate is commonly used in antacid medications because it can neutralize excess stomach acid.

Magnesium carbonate is the name of the compound being referred to in the question.

Silver hydroxide is not soluble in water. This is because silver hydroxide is a weak base and has low solubility in water. It forms a precipitate when dissolved in water, indicating that it is insoluble.

CaCO3 is a salt because it is composed of a metal ion (Ca2+) and a non-metal ion (CO32-). Salts are formed when a metal reacts with a non-metal, resulting in the transfer of electrons. In CaCO3, calcium (Ca) is a metal and carbonate (CO3) is a non-metal. Therefore, CaCO3 is a salt.

When electrolytes are dissolved in water, they break down into ions. These ions are electrically charged particles that can conduct electricity. Therefore, the correct answer is "ions."

An ionic compound is commonly referred to as salt because it is formed when a metal and a non-metal react and transfer electrons, resulting in the formation of positively and negatively charged ions that are held together by electrostatic forces. This arrangement closely resembles the structure of common table salt, which is made up of sodium and chloride ions. Therefore, "salt" is another name for an ionic compound.

When a salt comes out of solution, it forms a solid substance called a precipitate. A precipitate is formed when the salt molecules react with other molecules in the solution and create a new solid compound that is insoluble and separates from the liquid. Therefore, the correct answer is solid.

Trisulfur diphosphide is the name of the compound represented by the chemical formula S3P2. The name is derived from the elements present in the compound. "Tri" indicates the presence of three sulfur atoms, and "di" indicates the presence of two phosphorus atoms. Therefore, the compound is named trisulfur diphosphide.