Answer:
Qm = -55.8Kj/mole
Explanation:
NaOH(aq) + HNO₃(aq) => NaNO₃(aq) + H₂O(l)
Qm = (mc∆T)water /moles acid
Given => 100ml(0.300M) NaOH(aq) + 100ml(0.300M)HNO₃(aq)
=> 0.03mole NaOH(aq) + 0.03mole HNO₃(aq)
=> 0.03mole NaNO₃(aq) + 0.03mole H₂O(l)
ΔH⁰rxn = [(200ml)(1.00cal/g∙°C)(37 – 35)°C]water / 0.03mole HNO₃
= 13,333 cal/mole x 4.184J/cal = 55,787J/mol = 55.8Kj/mole (exothermic)*
Heat of reactions comes from formation of H-Oxy bonds on formation of water of reaction and heats the 200ml of solvent water from 35⁰C to 37⁰C.
Answer: 165.6grams
Explanation:
Mass of a block = ?
Volume of block = 18 cm^3
Density of block = 9.2 g/cm^3
The density of any object depends on its mass and volume.
i.e Density of block = Mass / volume
9.2 g/cm^3 = Mass / 18 cm^3
Mass = 9.2 g/cm^3 x 18 cm^3
= 165.6 g
Thus, the mass of the block is 165.6grams
Metallic ion because the metallic ions will enter an exited state and release photons energy, in the form of light, as they return to their ground state.
Answer:
The "2" applies only to the sodium, and sugar is a substance
Explanation:
The amount of atoms in an element are written using small letters after the element they refer to.
Answer:
mass Na2SO4 = 14.3816 g
Explanation:
sln Na2SO4:
∴ V = 450 mL
∴ <em>C </em>=<em> </em>0.2250 mol/L
∴ Mw ≡ 142.04 g/mol..... from literature
⇒ mol Na2SO4 = (0.2250 mol/L)(0.450 L) = 0.10125 mol
⇒ mass Na2SO4 = (0.10125 mol)(142.04 g/mol) = 14.3816 g
