Question is incomplete, the complete question is as follows:
A student wants to examine a substance by altering the bonds within its molecules. Which of the following properties of the substance should the student examine?
A. Toxicity, because it can be observed by altering the state of the substance
B. Boiling point, because it can be observed by altering the state of the substance
C. Toxicity, because it can be observed by replacing the atoms of the substance with new atoms
D. Boiling point, because it can be observed by replacing the atoms of the substance with new atoms
Answer:
B.
Explanation:
A student can examine a substance without altering the bonds within the molecules by examining its boiling point.
The boiling point is the property of a substance, at which the substance changes its state, which is from solid to liquid, liquid to gas and others. So, examining the boiling point will alter the bonds within the molecules as the state of substance will change.
Hence, the correct answer is "B".
The first law of thermodynamics characterises the two types of energy transfer, as heat and as thermodynamic. The final internal (thermal) energy of the system is 1,500 J.
<h3>What is internal energy?</h3>
The energy present in a system itself for conducting reactions is called internal energy.
Given,
- Heat entering system (Q) = 700 J
- Work done by the piston (W) = 400
- Initial energy
= 1200 J
According to the <u>first law of thermodynamics</u>:

Substituting values in the above equation:

Therefore, option D. 1500 J is the final energy.
Learn more about internal energy here:
brainly.com/question/2602565
Butterflies are cold-blooded and need the light from the sun to warm the muscles they use to fly. Not only do butterflies like the sun, the plants the they thrive on need full direct sun. Most plants need at least 8 hours of sunlight to bloom properly and provide enough nectar.
Among the choices, the only one that can be considered a carnivore is C. Adelie penguin. Adelie penguins are found in the Arctic, and feed on aquatic creatures such as krill, fish, and squid. Krill is a type of crustacean that feeds on phytoplankton, which is at the bottom of the food chain.