<h3>
Answer:</h3>
0.699 mole CaCl₂
<h3>
Explanation:</h3>
To get the number of moles we use the Avogadro's number.
Avogadro's number is 6.022 x 10^23.
But, 1 mole of a compound contains 6.022 x 10^23 molecules
In this case;
we are given 4.21 × 10^23 molecules of CaCl₂
Therefore, to get the number of moles
Moles = Number of molecules ÷ Avogadro's constant
= 4.21 × 10^23 molecules ÷ 6.022 x 10^23 molecules/mole
= 0.699 mole CaCl₂
Hence, the number of moles is 0.699 mole of CaCl₂
Calcium ions have oxidation state 2+ => Ca (2+).
Bromime ions (bromide) have oxidation state 1- => Br (-).
So, to be neutral the compound has to have two Br (-) ions per each Ca(2+) ion.
That is represented in the chemical formula as Ca Br2, where the number 2 to the right of Br is a subscript meaning that there are two atoms of Br per each atom of Ca (the lack of subscript means 1 atom).
Answer: Ca Br2.
<u>Answer:</u> The number of carbon, hydrogen and oxygen atoms on the left side of the reaction are 12, 28 and 38 respectively
<u>Explanation:</u>
In a chemical equation, the chemical species are termed as reactants or products.
Reactants are defined as the species which react in the reaction and are written on the left side of the reaction arrow.
Products are defined as the species which are produced in the reaction and are written on the right side of the reaction arrow.
For the given chemical equation:

On the reactant side:
Number of carbon atoms = (6 × 2) = 12
Number of hydrogen atoms = (14 × 2) = 28
Number of oxygen atoms = (2 × 19) = 38
Hence, the number of carbon, hydrogen and oxygen atoms on the left side of the reaction are 12, 28 and 38 respectively
Answer : 1721.72 g/qt are in 18.2 g/cL
Explanation :
As we are given: 18.2 g/cL
Now we have to convert 18.2 g/cL to g/qt.
Conversions used are:
(1) 1 L = 100 cL
(2) 1 L = 1000 mL
(3) 1 qt = 946 qt
The conversion expression will be:


Therefore, 1721.72 g/qt are in 18.2 g/cL
The more numbers after the decimal point there are, the more precise the instrument which recorded it is. For example, if one instrument during seismic activity records that the magnitude of the earthquake was 2.3, and another instrument recorded that it was 2.3645, the second instrument would have shown to be more precise.