Nokea
What is a benefit of water's ability to make hydrogen bonds?
- A. Lack of cohesiveness
- B. Low surface tension
- C. Use as a nonpolar solvent
- D. High specific heat
Correct Answer: D
Rationale: The correct answer is D - High specific heat. Water's ability to make hydrogen bonds leads to a high specific heat capacity, which allows it to absorb and release large amounts of heat with minimal temperature change. This property is crucial for maintaining stable temperatures in living organisms and aquatic environments. High specific heat helps regulate body temperature in organisms and prevents sudden temperature fluctuations in water bodies, providing an essential benefit for various biological processes.
You may also like to solve these questions
What are bases or alkaline solutions known as?
- A. Hydrogen acceptors
- B. Solutions of low pH
- C. Hydrogen donors
- D. Amphoteric
Correct Answer: A
Rationale: Bases or alkaline solutions are substances that can accept protons (H+ ions), making them hydrogen acceptors. When a base reacts with an acid, it accepts a proton to form water, hence neutralizing the acid. This property distinguishes bases from acids, which donate protons (H+ ions). Therefore, the correct answer is that bases or alkaline solutions are known as hydrogen acceptors.
Which statement is true regarding combination reactions?
- A. Involve only one reactant.
- B. Involve an element and an ionic compound.
- C. Form only one product.
- D. Require oxygen gas.
Correct Answer: C
Rationale: In a combination reaction, two or more substances combine to form a single product. This reaction type does not always involve only one reactant (choice A), an element and an ionic compound (choice B), or require oxygen gas (choice D). The true characteristic of combination reactions is that they form only one product, making choice C the correct answer.
What is 119°K in degrees Celsius?
- A. 32°C
- B. -154°C
- C. 154°C
- D. -32°C
Correct Answer: B
Rationale: The correct answer is 'B: -154°C.' To convert Kelvin to Celsius, you subtract 273.15 from the temperature in Kelvin. For 119°K: 119 - 273.15 = -154.15. Thus, 119°K is equal to approximately -154°C.
Which of the following describes atomic mass?
- A. Mass of protons and electrons
- B. Mass of neutrons and electrons
- C. Average mass of that element's isotopes
- D. Number of moles in a solution
Correct Answer: C
Rationale: The correct answer is C: Average mass of that element's isotopes. Atomic mass is the weighted average mass of the isotopes of an element, considering the natural abundance of each isotope. It is not just the sum of protons and neutrons or neutrons and electrons. Understanding atomic mass is crucial in chemistry as it helps in determining the molar mass of elements, which is essential in various chemical calculations such as stoichiometry and reaction equations.
What is the building block of proteins?
- A. Lipids
- B. Amino acids
- C. DNA
- D. Cells
Correct Answer: B
Rationale: Amino acids are the fundamental building blocks of proteins. Proteins are large biomolecules made up of one or more chains of amino acids. Each amino acid contains an amine group, a carboxylic acid group, and a side chain specific to each amino acid. When amino acids link together through peptide bonds, they form proteins. Lipids are a different type of biomolecule that includes fats, oils, and phospholipids. DNA is a nucleic acid that carries genetic information but is not directly involved in the structure of proteins. Cells are the basic structural and functional units of living organisms, not the building blocks of proteins.