Answer:
Chemical reactions that absorb (or use) energy overall are called endothermic. In endothermic reactions, more energy is absorbed when the bonds in the reactants are broken than is released when new bonds are formed in the products.
I guess the answer <span>can be an alkali metal, alkaline earth metal, or transition metals.
Hope this helps :)
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Answer:
-3.82ºC is the freezing point of solution
Explanation:
We work with the Freezing point depression to solve the problem
ΔT = m . Kf . i
ΔT = Freezing point of pure solvent - freezing point of solution
Let's find out m, molality (moles of solute in 1kg of solvent)
15 g / 58.45 g/mol = 0.257 moles of NaCl
NaCl(s) → Na⁺ (aq) + Cl⁻(aq)
i = 2 (Van't Hoff factor, numbers of ions dissolved)
m = mol /kg → 0.257 mol / 0.250kg = 1.03 m
Kf = Cryoscopic constant → 1.86 ºC/m (pure, for water)
0ºC - Tºf = 1.03m . 1.86ºC/m . 2
Tºf = -3.82ºC
Answer:
- 20 J
Explanation:
Heat of Reaction = Heat of Products - Heat of Reactants
From the graph;
Heat of Products = 10
Heat of Reactants = 30
Heat of Reaction = 10 - 30 = -20 J
