Acertain metal alloy is composed of 10% tin, 16% antimony, and 74% lead. if you were to have 500 g of the alloy, how many grams of antimony would be found in this sample?
a. 370g
b.50g
c.80g
d. 16g

c. 80 g

Explanation:

metal alloy:

for antimony:

⇒ 16% = (g antimony / g alloy)×100

⇒ 0.16 = g antimony / g alloy

∴ g alloy = 500 g

⇒ (0.16)×(500 g) = g antimony

⇒ g antimony = 80 g

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.