Question

loren has the samples of elements that are listed below at room temperature. he exposes the samples to the same heat source until each sample reaches a temperature of 90.0°c. 10 g of al(s) (cₚ = 0.897 j/(g,°c)) 10 g of ag(s) (cₚ= 0.234 j/g,°c ) 10 g of fe(s) (cₚ = 0.450 j/g,°c) 10 g of zn(s) (cₚ = 0.387 j/g,°c ) from first to last, which lists the order in which these samples will reach 90.0°c? ○ al, fe, zn, ag ○ ag, zn, fe, al ○ al, fe, ag, zn ○ ag, al, zn, fe

Explanation:

Step1: Recall the heat formula

The heat absorbed \( q = mC_p\Delta T \). Since \( m \) (mass) and \( \Delta T \) (change in temperature, \( 90.0 - \text{room temp} \), same for all) are constant, \( q \) is proportional to \( C_p \). Lower \( C_p \) means less heat needed, so faster heating.

Step2: Order \( C_p \) values

\( C_p \) values: \( \text{Ag}=0.234 \), \( \text{Zn}=0.387 \), \( \text{Fe}=0.450 \), \( \text{Al}=0.897 \). Lower \( C_p \) first. So order: Ag (lowest \( C_p \)), Zn, Fe, Al (highest \( C_p \)).

Answer:

B. Ag, Zn, Fe, Al