<h3><u>Answer;</u></h3>
CO3^2- and O3
<h3><u>Explanation;</u></h3>
- Ozone, O3 is a molecule composed of three oxygen atoms joined together. Two oxygen atoms joined together form the basic oxygen molecule O2.
- A polyatomic ion is a charged particle which has two or more atoms held together by covalent (sharing of pairs of electrons) bonds.
- Carbonate (CO3^2-) is an example of polyatomic ion. It can not be adequately described using Lewis structure.
Answer:
Standard pressure is always 1.00atm. Example #1: How many moles of oxygen will occupy a volume of 2.50 L at STP? Standard temperature = 273K law.
Explanation:
Answer:
a)


b)
Sulphurdioxide
c)


d)
Incomplete combustion produce harmful gases.
Explanation:
a)
Carbon reacts with atmospheric oxygen to form carbondioxide as well as sulphur dioxide.
The chemical equations are as follows.


b)
Sulfur dioxide is very harmful to the environment to cause acid rains.
This harmful gas mix with rain water to form sulphuric acid.
c)
The balanced chemical equation for the reaction that produces harmful environmental effects is as follows.



d)
In the absence of proper amount of oxygen required for combustion, incomplete combustion will take place which will result in formation of more carbondioxide an other harmful gases.
B.) Index of refraction of the second medium is higher
Answer:
4.5 × 10²³ number of atoms Al
Explanation:
Given data:
Mass of Al = 20 g
Number of atoms of Al = ?
Solution:
The given problem will solve by using Avogadro number.
'It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance" .The number 6.022 × 10²³ is called Avogadro number.
We will calculate the number of moles of Al first:
Number of moles = mass/molar mass
Number of moles = 20 g/ 27 g/mol
Number of moles = 0.74 mol
1 mole = 6.022 × 10²³ number of atoms
0.74 mol × 6.022 × 10²³ number of atoms / 1 mol
4.5 × 10²³ number of atoms Al