Chemical,when you light a match stick, you are starting a chain reaction of the substance chemical formula, making it a chemical change
Answer:
Mass = 65.8 g
Explanation:
Given data:
Mass of sodium chloride = ?
Volume of solution = 1.5 L
Molarity of solution = 0.75 M
Solution:
Number of moles of sodium chloride:
Molarity = number of moles / volume in L
By putting values,
0.75 M = number of moles = 1.5 L
Number of moles = 0.75 M × 1.5 L
Number of moles = 1.125 mol
Mass of sodium chloride:
Mass = number of moles × molar mass
Mass = 1.125 mol × 58.5 g/mol
Mass = 65.8 g
Answer:
ΔH3 = 1/2 (629) - ΔH^0
Explanation:
Given data:
Bond energy of H2 = ΔH1 = 436 Kj/mol
Bond energy of Br2 = ΔH2 = 193 Kj/mol
To find:
Let bond energy of HBr = ΔH3 = ?
Equation:
H2 + Br2 → 2HBr
enthalpy of formation of HBr = ΔH1 + ΔH3 - 2(ΔH3)
ΔH^0 = 436 + 193 - 2(ΔH3)
(436 + 193) - ΔH^0 = 2(ΔH3)
ΔH3 = 1/2 (629) - ΔH^0
Answer:
The correct option is: B. 13g
Explanation:
Given: Molar mass of iron (II) sulfate: m = 260g/mol,
Molarity of iron (II) sulfate solution: M = 0.1 M,
Volume of iron (II) sulfate solution: V = 500 mL = 500 × 10⁻³ = 0.5 L (∵ 1L = 1000mL)
Mass of iron (II) sulfate taken: w = ? g
<em>Molarity</em>: 
Here, n- total number of moles of solute, w - given mass of solute, m- molar mass of solute, V- total volume of solution in L
∴ <em>Molarity of iron (II) sulfate solution:</em> 
⇒ 
⇒ 
⇒ <em>mass of iron (II) sulfate taken:</em> 
<u>Therefore, the mass of iron (II) sulfate taken for preparing the given solution is 13 g.</u>