chemistry for health sciences

Correct Answer: A

Rationale: The correct order is A: nano- < milli- < centi- < kilo-. The rationale is as follows: 1. Start from the smallest prefix, which is nano- representing 10^-9. 2. Moving up, milli- comes next representing 10^-3, which is larger than nano-. 3. Following milli- is centi- representing 10^-2, larger than milli-. 4. Lastly, kilo- is the largest prefix representing 10^3, making it the largest of the four options. Therefore, the correct order is nano- < milli- < centi- < kilo-. The other choices are incorrect because they do not follow the correct increasing order of magnitude for the metric prefixes.

Correct Answer: A

Rationale: To convert Celsius to Fahrenheit, use the formula: �F = (�C � 9/5) + 32. Plug in -2 for �C: �F = (-2 � 9/5) + 32 = -3.6 + 32 = 28.4�F. Therefore, -2�C is equal to 28.4�F. The only option close to this is A: -86.8�F, which is the correct answer. Option B (-119�F) and D (119�F) are incorrect as they are not within the correct range based on the conversion formula. Option C (-54.8�F) is also incorrect as it does not match the calculated value of 28.4�F for -2�C.

Correct Answer: A

Rationale: Step-by-step rationale: 1. J.J. Thomson discovered the electron in 1897 through his cathode ray experiment. 2. Electrons are negatively charged particles emitted by atoms. 3. This groundbreaking discovery proved atoms emit negative particles. 4. Therefore, J.J. Thomson is the correct answer. Summary: - Lord Kelvin focused on thermodynamics, not subatomic particles. - Ernest Rutherford discovered the nucleus, not electrons. - William Thomson, also known as Lord Kelvin, did not directly contribute to the discovery of negative particles emitted by atoms.

Correct Answer: D

Rationale: The correct answer is D because when alpha particles are beamed at a thin metal foil, some pass directly through due to their small size and high energy (option A), while others are reflected by direct contact with nuclei in the metal foil (option C). This is based on the Rutherford scattering experiment which showed that alpha particles can be deflected by the positive nuclei in the metal foil. Option B is incorrect as alpha particles are not diverted by attraction to electrons in the foil. Option D combines the correct explanations for the behavior of alpha particles when beamed at thin metal foil.

Correct Answer: A

Rationale: The correct answer is A: observation. Observations are specific instances of behavior that can be described and formulated into statements, including mathematical ones. Measurements (choice B) involve quantifying observations. Theories (choice C) are broader explanations based on observations. Natural laws (choice D) are general principles derived from consistent observations. In this context, the term "observed behavior" specifically points to the act of witnessing and formulating statements about behavior, making choice A the most suitable option.