Answer: After three half-lives 1/8 (12.5%) of the original sample remains
<u>Answer:</u> The weak bond having slightly positive region and a slightly negative region is polar covalent bond.
<u>Explanation:</u>
Covalent bond is defined as the bond which is formed by the sharing of electrons between the atoms. <u>For Example:</u> HCl, 
etc..
They are of two types:
- <u>Polar covalent bond:</u> This bond is formed when difference in electronegativity between the atoms is present. When atoms of different elements combine, it results in the formation of polar covalent bond.
In this bond, a dipole is created. More electropnegative atom will have a slight negative charge and less electronegative atom will have a slight positive charge. For Example: 
etc..
- <u>Non-polar covalent bond:</u> This bond is formed when there is no difference in electronegativity between the atoms. When atoms of the same element combine, it results in the formation of non-polar covalent bond. For Example:
etc..
Hence, the weak bond having slightly positive region and a slightly negative region is polar covalent bond.
The answer is: emitted gas is carbon dioxide (CO₂).
Neutralization is is reaction in which an acid (in this example vinegar or acetic acid CH₃COOH) and a base (in this example soda)
Balanced chemical reaction of vinegar and antacid:
CH₃COOH(aq) + NaHCO₃(aq) → CH₃COONa(aq) + H₂O(l) + CO₂(g).
Sodium acetate (CH₃COONa) is a salt.
Sodium bicarbonate (NaHCO₃) is an antacid. Sodium bicarbonate is the active ingredient in baking soda.
Answers:
<span>Answer 1: 10.03 g of siver metal can be formed.</span>
Answer 2: 3.11 g of Co are left over.
Work:
1) Unbalanced chemical equation (given):
<span>Co + AgNO3 → Co(NO3)2 + Ag
2) Balanced chemical equation
</span>
<span>Co + 2AgNO3 → Co(NO3)2 + 2Ag
3) mole ratios
1 mol Co : 2 mole AgNO3 : 1 mol Co(NO3)2 : 2 mol Ag
4) Convert the masses in grams of the reactants into number of moles
4.1) 5.85 grams of Co
# moles = mass in grams / atomic mass
atomic mass of Co = 58.933 g/mol
# moles Co = 5.85 g / 58.933 g/mol = 0.0993 mol
4.2) 15.8 grams of Ag(NO3)
# moles Ag(NO3) = mass in grams / molar mass
molar mass AgNO3 = 169.87 g/mol
# moles Ag(NO3) = 15.8 g / 169.87 g/mol = 0.0930 mol
5) Limiting reactant
Given the mole ratio 1 mol Co : 2 mol Ag(NO3) you can conclude that there is not enough Ag(NO3) to make all the Co react.
That means that Ag(NO3) is the limiting reactant, which means that it will be consumed completely, whilce Co is the excess reactant.
6) Product formed.
Use this proportion:
2 mol Ag(NO3) 0.0930mol Ag(NO3)
--------------------- = ---------------------------
2 mol Ag x
=> x = 0.0930 mol
Convert 0.0930 mol Ag to grams:
mass Ag = # moles * atomic mass = 0.0930 mol * 107.868 g/mol = 10.03 g
Answer 1: 10.03 g of siver metal can be formed.
6) Excess reactant left over
1 mol Co x
----------------------- = ----------------------------
2 mole Ag(NO3) 0.0930 mol Ag(NO3)
=> x = 0.0930 / 2 mol Co = 0.0465 mol Co reacted
Excess = 0.0993 mol - 0.0465 mol = 0.0528 mol
Convert to grams:
0.0528 mol * 58.933 g/mol = 3.11 g
Answer 2: 3.11 g of Co are left over.
</span>
At room temperature hydrogen chloride is a colorless gas with a sharp or pungent odor. Under pressure or at temperatures below –85°C (-121°F), it is a clear liquid.
