Answer:
3
Explanation:
look after DP theres 3 digits
Answer:
When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt. The H(+) cation of the acid combines with the OH(-) anion of the base to form water. The compound formed by the cation of the base and the anion of the acid is called a salt.
Explanation:
1. There are 41.99 grams in 4.5 moles of sodium fluoride.
2. There are 1.26 moles in 98.3 grams of aluminum hydroxide.
3. There are 5 grams in 0.02 moles of beryllium iodide.
4. There are 0.70 moles in 68 grams of copper (II) hydroxide.
5. There are 0.064 grams in 2.3x10^-4 moles of calcium phosphate.
Answer:
A. 8.8 g.
B. 5.3 g.
C. 449 g.
Explanation:
A. Determination of the mass of CO2.
Mole of CO2 = 0.2 mole
Molar mass of CO2 = 12 + (2×16)
= 12 + 32
= 44 g/mol
Mass of CO2 =?
Mole = mass /Molar mass
0.2 = mass of CO2 /44
Cross multiply
Mass of CO2 = 0.2 × 44
Mass of CO2 = 8.8 g
B. Determination of the mass of Na2CO3.
Mole of Na2CO3 = 0.05 mole
Molar mass of Na2CO3 = (2×23) + 12 + (3×16)
= 46 + 12 + 48
= 106 g/mol
Mass of Na2CO3 =?
Mole = mass /Molar mass
0.05 = mass of Na2CO3 /106
Cross multiply
Mass of Na2CO3 = 0.05 × 106
Mass of Na2CO3 = 5.3 g
C. Determination of the mass of Fe(OH)2.
Mole of Fe(OH)2 = 5 moles
Molar mass of Fe(OH)2 = 55.8 + 2(16 + 1)
= 55.8 + 2(17)
= 55.8 + 34
= 89.8 g/mol
Mass of Fe(OH)2 =?
Mole = mass /Molar mass
5 = mass of Fe(OH)2/89.8
Cross multiply
Mass of Fe(OH)2 = 5 × 89.9
Mass of Fe(OH)2 = 449 g.
When an iron object is left in damp air for a considerable time, it gets covered with a reddish- brown flaky substance called rust. ... Rusting of iron is a chemical change because a new substance iron oxide is formed. The presence of oxygen and water or water vapour is essential for rusting.
