What type of reaction is described by the following equation? ZnBr2(aq) + 2KOH(aq) → Zn(OH)2(s) + 2KBr(aq)
A. Synthesis
B. Decomposition
C. Single-Replacement
D. Double-Replacement
In this reaction, two elements are trading places hence double-replacement. In the reactants, zinc and bromide ions are together, and potassium and hydroxide ions are together. In the products, zinc and hydroxide ions are together, and potassium and bromide ions are together.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: In which state of matter do the particles of iron have the lowest amount of cohesion?
A. Solid iron particles have the lowest amount of cohesion
B. Liquid iron particles have the lowest amount of cohesion
C. Gaseous iron particles have the lowest amount of cohesion
D. The particles have the same amount of cohesion in all states of matter.
Answer Explanation
The particles in a sample of gas are farther apart than in solids or liquids and therefore have the lowest amount of cohesion.
- Cohesion is the tendency of particles of the same kind to stick to each other.
- A solid has the lowest amount of energy because its particles are packed close together. Liquids have more energy than a solid, and gases have more energy than solids or liquids because the cohesive forces are very weak.
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Q #2: During which of the following phase changes will the cohesion between the particles in a substance decrease?
A. Condensation
B. Deposition
C. Freezing
D. Vaporization
Answer Explanation
If the cohesion between particles decreases, then the particles must be undergoing a phase change that allows particles to move farther apart. This happens when a substance vaporizes and turns from liquid to gas. Any phase change that moves to the right in the diagram above requires energy to be added to the system because the substance has more energy at the end of the phase change. The phase changes are melting, vaporization (boiling), and sublimation. When energy is added, particles move faster and can break away from each other more easily as they move to a state of matter with a higher amount of energy. This is most commonly done by heating the substance.
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Q #3: What is the final structure through which urine must travel to empty out of the body?
A. Bladder
B. Kidney
C. Ureter
D. Urethra
Answer Explanation
The primary organ of the urinary system is the kidney. Blood from the heart flows through the kidneys via the renal artery. As blood drains from the kidney, it exits through a series of veins, the most prominent of which is the renal vein. When urine is produced, it does not drain through the tubes through which blood flows. Rather, urine flows through two ureters before emptying into the urinary bladder.
The following steps outline how the urinary system works:
- Kidney filters and excretes wastes from blood, producing urine.
- Urine flows down the ureters.
- Urine empties into the bladder and is temporarily stored.
- Bladder, when filled, empties urine out of the body via the urethra.
