Answer:
D is the correct answer.
Explanation:
I took the test on A pex. Everyone make sure you look at your answers. They are NOT always in the same order.
Answer:
democritus is the first person
When sugar is heated it melts and then caramelize giving of water. After this, it turns blank (carbon) and then coverts to co2 (carbon dioxide) .
So, heating of sugar is an endothermic , decomposition and oxidation reaction.
When Ammonium Chloride is heated , it directly goes from solid state to vapour state without changing into liquid state.
So, heating of Ammonium Chloride is an example of sublimation reaction.
Answer:
209.98 g of NaOH
Explanation:
We are given;
- Volume of HCl as 3 L
- Molarity of HCl as 1.75 M
We are required to calculate the mass of NaOH required to completely neutralize the acid given.
First, we write a balanced equation for the reaction between NaOH and HCl
That is;
NaOH + HCl → NaCl + H₂O
Second, we determine the number of moles of HCl
Number of moles = Molarity × Volume
= 1.75 M × 3 L
= 5.25 moles
Third, we use the mole ratio to determine the moles of NaOH
From the reaction,
1 mole of NaOH reacts with 1 mole of HCl
Therefore;
Moles of NaOH = Moles of HCl
= 5.25 moles
Fourth, we determine the mass of NaOH
Molar mass of NaOH = 39.997 g/mol
Mass of NaOH = 5.25 moles × 39.997 g/mol
= 209.98 g
Thus, 209.98 g of NaOH will completely neutralize 3L of 1.74 M HCl
Answer:
The charge carried by each ion (oxidation state of each atom)
Explanation:
If we have an ionic compound and we want to write its formula, we must first know the magnitude of charge on each ion (shown as oxidation state of the atoms involved) because the magnitude of charge on each ion is eventually crisscrossed and gives the subscript (number of atoms) for each atom in the formula.
For instance, let us write the formula of calcium bromide. Ca has a charge of +2 while Br has a charge of -1. If we exchange the charges and ignore the signs such that the crisscrossed charges form subscripts we can now write; 
.
