- A chemical reaction is considered as a process of transformation of chemical reactants into products.
- Chemical reactions involve change in position of electrons or breaking the bonds between atoms to form new molecules. (no change in the elements present).
- Chemical reactions are best described by chemical equations
So the correct answer is B
Answer:
To keep the evinermental machinces working
Explanation:
<em>Answer:</em>
- 0.052301 km have 5 significant figure
- 400 cm have 1 significant figure
- 50.0 m have 3 significant figure
- 4500.01 ml have 6 significant figure
<em>Explanation:</em>
According to rules of significant figure
0.052301 km have 5 significant figure:
- Zero to the left of the first non zero digit not significant.
- Zero between the non zero digits are significant.
<em>400 cm have 1 significant figure:</em>
- Trailing zeros are not significant in numbers without decimal points.
<em>50.0 m have 3 significant figure:</em>
- Trailing zeros are significant in numbers when there is decimal points.
<em>4500.01 ml have 6 significant figure:</em>
- Zero between the non zero digits are significant.
Answer:
1. Hydrogen ions; acidic
2. Alkali; hydroxide ions; alkaline
3a. Sulfuric acid --> 2 Hydrogen ions + sulfate ion
H₂SO₄ --> 2H+ + SO₄²-
3b. Sodium hydroxide --> Sodium ion + Hydroxide ion
NaOH --> Na+ + OH-
Explanation:
1. Sulfuric acid releases hydrogen ions in solution. This makes the solution acidic.
Acids produce hydrogen ions when dissolved in aqueous solutions.
2. Sodium hydroxide is an alkali. It releases hydroxide ions in solution. This makes the solution alkaline.
Alkalis are soluble bases that produce hydroxide ions in solution.
3a. Sulfuric acid --> 2 Hydrogen ions + sulfate ions
H₂SO₄ --> 2H+ + SO₄²-
The equation above is for the ionization of sulfuric acid
b. Sodium hydroxide --> Sodium ion + Hydroxide ion
NaOH --> Na+ + OH-
The equation above is for the ionization of sodium hydroxide
Answer:
Mass of barium sulfate = 8.17 g
Explanation:
Given data:
Mass of sodium sulfate = 4.98 g
Mass of barium sulfate produced = ?
Solution:
Na₂SO₄ + Ba(NO₃)₂ → BaSO₄ + 2NaNO₃
Moles of sodium sulfate:
Number of moles = mass/molar mass
Number of moles =4.98 g / 142.04 g/mol
Number of moles = 0.035 mol
Now we will compare the moles pf sodium sulfate and with barium sulfate.
Na₂SO₄ : BaSO₄
1 : 1
0.035 : 0.035
Mass of barium sulfate:
Mass = number of moles × molar mass
Mass = 0.035 mol ×233.4 g/mol
Mass = 8.17 g
