Which property can be used to distinguish talc from gypsum?
gypsum has a soapy feel.

talc has a soapy feel.

gypsum can scratch glass.

talc fizzes with hydrochloric acid.

B. Talc has soapy feel.

Explanation:

Gypsum is a hydrated calcium sulphate mineral .

The chemical formula of gypsum is

It consist of calcium, sulphur, oxygen and hydrogen.

It is soft sulphate mineral. It is used in plaster  formation. It is used  in blackboard chalk formation.It is used as a fertilizer.It Talc can not  scratch gypsum  because it is harder than talc.It has no soapy feel.

Talc is hydrous magnesium silicate mineral . It is usually green ,gray, white , brown or colourless.It is a translucent mineral . It has pearly luster.

It is soften known mineral. The chemical formula of talc is .It consist of magnesium, silicon, oxygen and hydrogen.It has extreme softness and greasy. It has soapy feel. Gypsum is harder than talc and more difficult to scratch.

Hence, the option B is true.

B. Talc has soapy feel.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer