Astronomers classify stars according to their physical characteristics. Characteristics used to classify stars include color, temperature, size, composition, and brightness. Stars vary in their chemical composition.
Some laces get warm and some get cold
Question 3
Explanation:
answer -A /A chemical reaction happens when substances break apart or combine to form one or more new substances. New substances form when bonds break and new bonds form. The chemical properties of the new substances are different from those of the original substances. ... Some chemical reactions produce a precipitate.
answer- B /Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products
Answer:
81 molecules
Explanation:
The reaction between C5H12 and O2 is a combustion reaction and is represented by the following equation;
C5H12 + 8O2 --> 5CO2 + 6H2O
The ratio of C5H12 to O2 from the above equation is 1 : 8.
Aplying the conditins of the question; 24 molecules each of C5H12 and O2 we have;
3C5H12 + 24O2 --> 15CO2 + 18H2O
This means we have 24 - 3 = 21 molecules of C5H12 that are unreacted.
Total molecules is given as;
3(C5H12) + 24(O2) + 15(CO2) + 18(H2O) + 21(Unreacted C5H12) = 81 molecules
If it is heated while it is being compressed or held inside a container as such, the pressure build up while in the container and the pressure can become so much that the container will burst.
