Answer:
Molecules are made of two or more atoms
Molecules are made of atoms of the same element or different elements.
Molecules range in size.
Explanation:
A molecule is formed whenever two or more atoms combine. Hence we can define a molecule as a combination of two or more elements that are combined chemically and can not be separated by any physical means.
Molecules may be composed of the same atoms as in O2, F2 etc or different atoms as in CO2, H2O, etc.
The sizes of molecules differ. Some molecules are quite small in size while others are quite large in size.
Answer:
c
Explanation:
use %composition given to calculate emperical 4mular
Answer:
Aspirin was purified in the lab by recrystallizing the crude aspirin. The melting point of the purified aspirin is expected to be lower than the melting point of crude aspirin.
Explanation:
The presence of impurities in a sample lowers the melting point of the impure substance. Hence the melting point of an impure substance is always less than the melting point of the corresponding pure substance.
Bearing this in mind, the statement "Aspirin was purified in the lab by recrystallizing the crude aspirin. The melting point of the purified aspirin is expected to be lower than the melting point of crude aspirin." is found to be false since impure substances tend to have a slightly lower melting point than the pure substance, and a broader melting temperature range.
The average atomic mass of oxygen is the atomic mass with respect to 1/12th the mass of a C-12 atom, related to natural abundance.
amu - atomic mass units
O-16 - 15.995 amu
O-17 - 16.999 amu
O-18 - 17.999 amu
the average atomic mass is 15.9994 amu
average atomic mass = ∑atomic mass of each isotope * relative abundance percentage
in other words the average atomic mass is closer to the atomic mass of the most abundant isotope. In this case 15.9994 is closest to 15.995 amu which is the atomic mass of O-16.
This means that O-16 is the most abundant isotope.
Answer:
table A
Explanation:
its table A because it requires less force push. the less force used the less friction there is.
the less friction there is the more smooth a surface is.
