<u>Answer:</u>
Exothermic Reaction are those reaction, in which energy is released while in endothermic reaction are those, in which energy is absorbed.
<u>Explanation:</u>
First Reaction:
As in this reaction, energy is released
½H2(g) + ½I2(g) → HI(g), ΔH = +6.2 kcal/mole
so it is <em>exothermic reaction</em>
Second reaction:
As in this reaction, energy is absorbed
21.0 kcal/mole + C(s) + 2S(s) → CS2(l)
so it is <em>endothermic reactions</em>.
Answer:A cup of household bleach changes the color of your favorite T-shirt from purple to pink. - chemical change
Water vapor in your exhaled breath condenses in the air on a cold day.- physical change
Plants use carbon dioxide from the air to make sugar.- chemical change
Butter melts when placed in the Sun- physical change
Explanation:
A chemical change leads to the formation of a new substance and is not easily reversible. A physical change does not lead to the formation of a new substance and is easily reversible. Physical changes include condensation, melting,etc while a chemical change is a chemical reaction.
It creates chlorofluorocarbons(CFCs) also would create biooxygen but in the multiple choice it only shows the CFCs
Answer: 0.0 grams
Explanation:
To calculate the moles, we use the equation:
a) moles of butane
b) moles of oxygen
According to stoichiometry :
2 moles of butane require 13 moles of 
Thus 0.09 moles of butane will require =
of
Butane is the limiting reagent as it limits the formation of product and oxygen is present in excess as (1.02-0.585)=0.435 moles will be left.
Thus all the butane will be consumed and 0.0 grams of butane will be left.
Answer is: <span>Mutations sometimes improve the chances of survival for a plant.
</span>Mutations are very important because they change <span>variability in populations and in that way enable evolutionary change.
</span>There are three types of mutations:
1) good or advantageous mutations - <span> improve the chances of survival for a plant.
2) </span>bad or deleterious - decrease the chances of survival for a plant.
3) neutral - not affect he chances of survival for a plant.
