A homogeneous mixture is uniform throughout, like water that has dissolved gases. You cannot easily distinguish the individual parts of the mixture. Many other drinks are considered homogeneous too. Laundry detergent and colognes are other examples of homogeneous mixtures. Homogeneous mixtures can also be a solid (ie. steel), liquid or gas form. It does not always have to be a liquid.
The horizontal rows in the periodic table are periods, while the vertical rows are called groups. The elements moving from left to right in "periods" have increasing atomic numbers.
Answer is: d. 3,2,3.
Balanced chemical reaction: CH₃CH₂OH + 3O₂ → 2CO₂ + 3H₂O.
CH₃CH₂OH is ethanol.
O₂ is molecule of oxygen.
CO₂ is carbon(IV) oxide.
H₂O is water.
There are same number of atoms (oxygen, carbon and hydrogen) on both side of balanced chemical reaction:
2 atoms of carbon.
6 atoms of hydrogen.
7 atoms of oxygen.
Answer:
Approximately
.
Explanation:
Lookup Avogadro's Number:
(three significant figures.)
Lookup the relative atomic mass of
,
, and
on a modern periodic table:
(For example, the relative atomic mass of
is
means that the mass of one mole of
atoms would be approximately
grams on average.)
The question counted the number of
molecules without using any unit. Avogadro's Number
helps convert the unit of that count to moles.
Each mole of
molecules includes exactly
of these
molecules.
molecules would correspond to
of such molecules.
(Keep more significant figures than required during intermediary steps.)
The formula mass of
gives the mass of each mole of
molecules. The value of the formula mass could be calculated using the relative atomic mass of each element:
.
Calculate the mass of approximately
of
:
.
(Rounded to three significant figures.)