An iron block of mass 18 kg is heated from 285 K to 318 K. If 267.3 kJ is required, what is the specific heat of iron? A. 490.05
B. 158.77
C. 145.80
D. 450.00

D. 450 J/kgK

Explanation:

Using the formula as follows:

Q = m × c × ∆T

Where:

Q = amount of heat absorbed/released (J)

m = mass of substance (g)

c = specific heat capacity

∆T = change in temperature (°C)

According to the information provided in this question:

Q = 267.3 kJ = 267300J

m = 18kg

∆T = 318K - 285K = 33K

c = ?

Q = m × c × ∆T

c = Q ÷ m∆T

c = 267300 ÷ 18 × 33

c = 267300 ÷ 594

c = 450 J/kgK

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.