Talc is a mineral with low conductivity for heat and electricity which is not attacked by acid. it is used in talcum powder and
face powder. suppose a sample of talc weighs 13.65 g with a density of 1.75 g/cm3 in mineral oil. if this same sample of talc in air weighs 35.97 g, assuming no volume change, what is the density of the talc sample in air?
Answer is: density of the talc sample in air is 4,61 g/cm³. m(talc) = 13,65 g. d(talc) = 1,75 g/cm³. V(talc) = m(talc) ÷ d(talc). V(talc) = 13,65 g ÷ 1,75 g/cm³. V(talc) = 7,8 cm³. d(talc in air) = m(talc in air) ÷ V(talc). d(talc in air) = 35,97 g ÷ 7,8 cm³. d(talc in air) = 4,61 g/cm³.
The correct answer is elements in family 7 have similar properties because elements in the same group or family have the same number of valence electrons.
