Homogeneous Solution Quiz Questions

The equation identifies the reactants (starting materials) and products (resulting substance).

Digestion is an example of a decomposition reaction because it involves the breaking down of complex molecules into simpler substances. In the process of digestion, food is broken down into smaller molecules through the action of enzymes in the digestive system. This breakdown allows for the absorption and utilization of nutrients by the body.

The chemical equation provided is Na + O2 --> Na2O2. In order to balance the equation, we need to ensure that the number of atoms on both sides of the equation are equal. By placing a coefficient of 2 in front of Na, we have 2 Na atoms on both sides. By placing a coefficient of 1 in front of O2, we have 2 O atoms on both sides. Finally, by placing a coefficient of 1 in front of Na2O2, we have 2 Na atoms and 2 O atoms on both sides. Therefore, the coefficients that balance the equation are 2, 1, 1.

Rubbing alcohol is a homogeneous mixture because it is a solution of alcohol in water, where the alcohol molecules are evenly distributed throughout the water molecules. This means that the composition and properties of rubbing alcohol are consistent throughout, making it a homogeneous mixture. In contrast, salad dressing, gelatin, and orange juice with pulp are heterogeneous mixtures because they contain visible or distinguishable components that are not evenly distributed.

In the given reaction, 2 moles of water produce 2 moles of hydrogen gas. This is because the stoichiometric ratio between water and hydrogen gas is 1:1. Therefore, if we start with 2 moles of water, we will produce 2 moles of hydrogen gas.

A compound differs from a mixture because it always contains the same elements in the same proportion. This means that the ratio of the different elements in a compound is fixed and does not change. In contrast, a mixture can have varying ratios of different substances.

Table sugar, or sucrose (C12H22O11), is composed of 12 carbon atoms. This is because the formula C12H22O11 indicates that there are 12 carbon atoms in each molecule of table sugar.

The density of lead is given as 11.3 g/cm3. Density is defined as mass divided by volume. Therefore, to find the volume of the lead block, we can rearrange the equation to solve for volume. The mass of the lead block is given as 282.5 g. So, we can calculate the volume by dividing the mass by the density: 282.5 g / 11.3 g/cm3 = 25 cm3. Therefore, the volume of the lead block is 25 cm3.

Water is referred to as the universal solvent because it has the ability to dissolve a wide variety of substances. This is due to its unique molecular structure, which allows it to form hydrogen bonds with other molecules. These hydrogen bonds break apart the solute molecules and surround them with water molecules, effectively dissolving them. This property of water makes it an excellent solvent for many substances, including salts, sugars, and acids. Therefore, the correct answer is that many different substances dissolve in water.

In a balanced chemical reaction, the total mass of the products always equals the total mass of the reactants. This is because the law of conservation of mass states that matter cannot be created or destroyed in a chemical reaction, only rearranged. Therefore, the total mass of the reactants must be equal to the total mass of the products.

Covalent bonds are formed between nonmetal atoms. In a covalent bond, two atoms share electrons in order to achieve a stable electron configuration. Nonmetal atoms have a higher electronegativity, meaning they have a stronger attraction for electrons. This makes them more likely to share electrons with other nonmetal atoms rather than transferring them to form ionic bonds with metal atoms. Therefore, the correct answer is nonmetal atoms.

The mass number of an atom is the sum of the number of protons and neutrons in its nucleus. This is because protons and neutrons both contribute to the mass of an atom, while electrons have negligible mass compared to protons and neutrons. Therefore, the correct answer is "protons plus the number of neutrons".

Grinding quartz crystals down to produce sand is an example of a physical change because the substance (quartz) is being physically altered in form (from large crystals to small particles) without any change in its chemical composition. The molecules of quartz remain the same, only the arrangement and size of the particles change.

In a chemical reaction, atoms are rearranged. This means that the arrangement of atoms in the reactants is different from the arrangement of atoms in the products. However, no atoms are destroyed or created in a chemical reaction. The total number of atoms remains the same, but their arrangement and bonding change, resulting in the formation of new substances.

In a synthesis reaction, two or more compounds combine to form a new compound that is more complex than the original compounds. This process involves the rearrangement of atoms and the formation of new chemical bonds. This is different from a decomposition reaction where a compound breaks down into simpler substances. Therefore, the correct answer is that a new, more complex compound is formed in a synthesis reaction.

When potassium is placed in water, it reacts with water molecules to form potassium hydroxide (KOH) and hydrogen gas (H2). This type of reaction, where one element displaces another element in a compound, is called a single displacement reaction. In this case, potassium displaces hydrogen in water to form potassium hydroxide and hydrogen gas.

Mayonnaise is an example of a heterogeneous mixture because it is made up of two or more substances that are visibly different and do not blend together uniformly. In mayonnaise, the oil and vinegar do not fully mix and can be seen as separate layers or droplets within the mixture.

An ionic bond is a bond that forms between atoms with opposite charges. In this type of bond, one atom transfers electrons to another atom, resulting in the formation of positive and negative ions. The attraction between these ions then holds the atoms together, creating a strong bond. This is different from covalent bonds, where atoms share electrons. Therefore, atoms with opposite charges are able to form ionic bonds.

A heterogeneous mixture is one that is not uniform throughout, meaning that its components are not evenly distributed. This means that different parts of the mixture may have different properties or concentrations. In contrast, a homogeneous mixture is one that is uniform throughout, where the components are evenly distributed and the mixture has the same properties and concentrations in all parts.

A balanced chemical equation shows the proportions of reactants and products necessary for the reaction to occur. This means that the total mass of the reactants must be equal to the total mass of the products. This principle is known as the law of conservation of mass, which states that mass cannot be created or destroyed in a chemical reaction, only rearranged. Therefore, the correct answer is "mass to be conserved."