Which of the following atoms is a cation?
A. 14 protons, 14 neutrons, 18 electrons
B. 34 protons, 45 neutrons, 36 electrons
C. 35 protons, 44 neutrons, 35 electrons
D. 82 protons, 125 neutrons, 78 electrons
Because it has more protons than electrons, this atom has a positive charge and can be classified as a cation. When a metal such as sodium reacts to become stable, it loses its valence electrons. At first, it is a neutral atom with 11 protons and 11 electrons. When it loses an electron, the number of protons does not change, and the atom has 11 protons and 10 electrons. Because there is one more positively charged proton, a cation forms. A cation is an ion with a net positive charge.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: In which state of matter are the intermolecular forces between particles in a substance the strongest?
A. Gas
B. Liquid
C. Plasma
D. Solid
Answer Explanation
In solids, particles are usually closer together than in other states of matter because of the strong cohesive forces between the particles.
- Solids, liquids, gases, and plasmas differ from one another in the amount of energy that the particles have and the strength of the cohesive forces that hold the particles together.
- 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: What standard is used to make comparisons in experiments?
A. Sample size
B. Control group
C. Dependent variable
D. Independent variable
Answer Explanation
A control group is a factor that does not change during an experiment. Due to this, it is used as a standard for comparison with variables that do change such as a dependent variable.
Recall that these make up the scientific method, described below:
- Problem: The question created because of an observation. Example: Does the size of a plastic object affect how fast it naturally degrades in a lake?
- Research: Reliable information available about what is observed. Example: Learn how plastics are made and understand the properties of a lake.
- Hypothesis: A predicted solution to the question or problem. Example: If the plastic material is small, then it will degrade faster than a large particle.
- Experiment: A series of tests used to evaluate the hypothesis. Experiments consist of an independent variable that the researcher modifies and a dependent variable that changes due to the independent variable. They also include a control group used as a standard to make comparisons.
- Example: Collect plastic particles both onshore and offshore of the lake over time. Determine the size of the particles and describe the lake conditions during this time period.
- Observe: Analyze data collected during an experiment to observe patterns.
- Example: Analyze the differences between the numbers of particles collected in terms of size.
- Conclusion: State whether the hypothesis is rejected or accepted and summarize all results.
- Communicate: Report findings so others can replicate and verify the results.
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Q #3: What phase is the cell cycle part of?
A. Interphase
B. Metaphase
C. Prophase
D. Telophase
Answer Explanation
Before mitosis or meiosis occurs, interphase must happen. This is when the cell cycle takes place. The cell cycle is an organized process divided into two phases: interphase and the M (mitotic) phase. During interphase, the cell grows and copies its DNA. After the cell reaches the M phase, division of the two new cells can occur. The G1, S, and G2 phases make up interphase.
