HESI A2 Chemistry

Questions 33

HESI A2

HESI A2 Test Bank

HESI A2 Chemistry Questions

Question 1 of 5

How many protons does Potassium have?

Correct Answer: B

Rationale: The correct answer is B: 19 protons. Potassium's atomic number is 19, which represents the number of protons in its nucleus. Protons are positively charged particles in an atom. Option A (18) is incorrect as it does not match the atomic number of Potassium. Options C (20) and D (21) are also incorrect as they do not correspond to Potassium's atomic number. Thus, the correct answer is B (19) based on the periodic table.

Question 2 of 5

What type of chemical reaction is represented by AB → A + B?

Correct Answer: B

Rationale: The correct answer is B: Decomposition. In this reaction, a single reactant (AB) breaks down into two or more products (A and B). This aligns with the definition of a decomposition reaction, where a compound is broken down into simpler substances. Choice A (Synthesis) involves combining two or more substances to form a more complex product, which is not the case here. Choices C (Single replacement) and D (Double replacement) involve the exchange of ions or elements between compounds, which is not happening in the given reaction. Thus, based on the breakdown of reactants and products, the correct classification of the reaction is decomposition.

Question 3 of 5

What form of radiation is composed of electrons traveling at around 16,000 km/sec?

Correct Answer: B

Rationale: The correct answer is B: Beta radiation. Beta radiation consists of high-energy electrons or positrons traveling at high speeds, typically around 16,000 km/sec. This is because beta particles are emitted during the decay of a radioactive nucleus when a neutron changes into a proton and an electron (beta-minus decay) or a proton changes into a neutron and a positron (beta-plus decay). Alpha radiation (A) consists of helium nuclei, gamma radiation (C) is high-energy electromagnetic radiation, and there is no such thing as delta radiation (D) in the context of nuclear physics.

Question 4 of 5

What is the name of the compound CH₃-CH₂-CH₂-CH₃?

Correct Answer: B

Rationale: The correct answer is B: Butane. In this compound, CH₃-CH₂-CH₂-CH₃, there are four carbon atoms connected in a straight chain, making it a butane. The prefix "but-" indicates that there are four carbon atoms, and the suffix "-ane" indicates that the compound contains only single bonds between the carbon atoms. Therefore, the correct name is Butane. Choice A: Cyclobutane is incorrect because it would be a cyclic compound with four carbon atoms forming a ring. Choice C: Butene is incorrect because it would have a double bond between two carbon atoms, making it an alkene. Choice D: Butyne is incorrect because it would have a triple bond between two carbon atoms, making it an alkyne.

Question 5 of 5

Among the following elements, which is a nonmetal?

Correct Answer: C

Rationale: Step-by-step rationale: 1. Nonmetals are elements that lack metallic properties. 2. Sulfur is a nonmetal as it exists in a gaseous form at room temperature, lacks luster, and is a poor conductor of heat and electricity. 3. Mercury (A) is a metal as it is a liquid at room temperature. 4. Magnesium (B) and Potassium (D) are both metals as they are solid at room temperature and exhibit typical metallic properties. Summary: - A: Mercury is a metal. - B: Magnesium is a metal. - C: Sulfur is the correct answer as a nonmetal. - D: Potassium is a metal.

Similar Questions

Join Our Community Today!

Join Over 10,000+ nursing students using Nurselytic. Access Comprehensive study Guides curriculum for HESI A2-HESI A2 and 3000+ practice questions to help you pass your HESI A2-HESI A2 exam.

Call to Action Image