Answer: 1.41725 X 10^{24} atoms
Explanation:
One male of any gas containing no. of atoms
2.5 moles of gas containing no. of atoms
The given gas is triatomic gas. Hence
No. of atoms

Answer:
Sand (SiO2 silica) In its pure form it exists as a polymer, (SiO2)n.
Soda ash (sodium carbonate Na2CO3) ...
Limestone (calcium carbonate or CaCo3) or dolomite (MgCO3)
Explanation:
I am pretty sure you know what sand is, Soda ash is a fine white colored powder that is extracted from the ashes of plants growing in sodium rich soils. Limestone is is a common type of carbonate sedimentary rock.
Answer:
Iodide> Bromide > chloride > flouride
Explanation:
During a nucleophilic substitution reaction, a nucleophilie replaces another in a molecule.
This process may occur via an ionic mechanism (SN1) or via a concerted mechanism (SN2).
In either case, the ease of departure of the leaving group is determined by the nature of the C-X bond. The stronger the C-X bond, the worse the leaving group will be in nucleophilic substitution. The order of strength of C-X bond is F>Cl>Br>I.
Hence, iodine displays the weakest C-X bond strength and it is thus, a very good leaving group in nucleophillic substitution while fluorine displays a very high C-X bond strength hence it is a bad leaving group in nucleophilic substitution.
Therefore, the ease of the use of halide ions as leaving groups follows the trend; Iodide> Bromide > chloride > flouride
There are 4 electron pairs (3 bonding and 1 lone pair) so the angle is 107 degrees. The 4 electron pairs are repelled to give a tetrahedral arrangement but the molecule has a pyrimidal shape due to the lone pair.