The correct answer is option 1. When pellets of solid NaOH are added to water and stirred, the temperature of water increases because chemical energy is converted into heat energy. Dissolution of sodium hydroxide in water is an exothermic process where heat is dissipated.
Answer:
123456789dfghjk
Explanation:
gggyyhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhnnnnnnnnnnnnnnnnvvvvvvvvvvvvccccccccccccccxxxxxxxxxxzzszsdfvbhngyfdd
<span> 1C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O, the ∆H is –2200 kJ
1mol </span>C3H8(g) ---- –2200 kJ
2mol C3H8(g) ----2(–2200 kJ)=-4400kJ
To find molarity
1) number of mol of solute.
Solute is HCl.
M(HCl)= 1.0+35.5 =36.5 g/mol
25g *1 mol/36.5 g = 25/36.5 mol HCl
2) Molarity is number of mole of the solute in 1 L solution.
150 mL = 0.150 L
(25/36.5 mol HCl )/(0.150 L) = 25/(36.5*0.150) ≈ 4.57≈4.6 mol/L