Answer:
669.48 kJ
Explanation:
According to the question, we are required to determine the heat change involved.
We know that, heat change is given by the formula;
Heat change = Mass × change in temperature × Specific heat
In this case;
Change in temperature = Final temp - initial temp
= 99.7°C - 20°C
= 79.7° C
Mass of water is 2000 g ( 2000 mL × 1 g/mL)
Specific heat of water is 4.2 J/g°C
Therefore;
Heat change = 2000 g × 79.7 °C × 4.2 J/g°C
= 669,480 joules
But, 1 kJ = 1000 J
Therefore, heat change is 669.48 kJ
To calculate the mass of milk of magnesia given, we need certain data like molar mass of the compound which needs the atomic mass of the atoms in the compound. We calculate as follows:
Molar mass of <span>Mg(OH)2 = 24.3 g/mol + (2 x (16 + 1.0)) = 58.30 g/mol
Mass = 3.2 mol (</span>58.30 g/mol) = 186.56 grams
Answer:
525.1 g of BaSO₄ are produced.
Explanation:
The reaction of precipitation is:
Na₂SO₄ (aq) + BaCl₂ (aq) → BaSO₄ (s) ↓ + 2NaCl (aq)
Ratio is 1:1. So 1 mol of sodium sulfate can make precipitate 1 mol of barium sulfate.
The excersise determines that the excess is the BaCl₂.
After the reaction goes complete and, at 100 % yield reaction, 2.25 moles of BaSO₄ are produced.
We convert the moles to mass: 2.25 mol . 233.38 g/mol = 525.1 g
The precipitation's equilibrium is:
SO₄⁻² (aq) + Ba²⁺ (aq) ⇄ BaSO₄ (s) ↓ Kps
Answer:
The exact molecular mass is 18.01528 g/mol
Explanation:
Find this by adding the molecular masses of two hydrogen atoms and one oxygen atom.
The Blood Alcohol Level (BAC) will rise. Because it usually peaks about 30 minutes after drinking, a sharp spike at 20 minutes makes sense.
BAC.
