4 is correct for this one
265
your answer would be 265. Because the charge of +1 means there is one more proton then electron. So, 108 protons plus 157 neutrons gives you your mass number of 265.
Answer:
A.
Explanation:
A toxic substance is a substance that can cause some harmful effects when a person is exposed to it. The sum of all adverse effects is called the toxicity of a substance. As higher is the toxicity, as dangerous is the substance. The effects can be observed in the mouth, the eyes, the skin, the tract respiratory, the brain, etc.
A substance or agent that can interfere with normal embryonic development is called teratogenic.
A substance or agent capable of causing or producing cancer in mammals is called carcinogenic.
The dose found to be lethal in 50 percent of a group of test animals when administered by the specified route is called LD50 (Lethal Dose 50).
Answer:
Acids and bases are used in most many chemical reactions in chemistry . They are responsible for most colour changes in a chemical reaction and are used to adjust the pH of chemical solutions.
Explanation:
<span>Hello!
The statement that best proves that the law of conservation is obeyed during this process is that </span><span>The total mass of oxygen and carbon is equal to the total mass of carbon dioxide.
The chemical equation for the combustion reaction of coal in the carbon cycle is the following one:
C(s) + O</span>₂(g) → CO₂(g)
<span>
From this simple chemical equation, we can conclude that if the Law of Conservation of Matter is obeyed in this reaction, the sum of the initial masses of Carbon and Oxygen before the reaction will be equal to the total amount of Carbon Dioxide formed by it, because they sum up to produce Carbon Dioxide.
Have a nice day!</span>
