Chem question

bonkysleuth SG

Sulfur and chlorine can react together to form S2Cl2. When 1.00g of this sulfur chloride reacted with water, 0.36g of a yellow ppt of sulfur was formed together with a solution contianing a mixture of sulfurous acid, H2SO3, and HCl acid. Use the above data to deduce the equation for the reaction between S2Cl2 and water [S = 32.1; Cl = 35.5]

i find the no. of moles of S2Cl2 and sulfur itself. Following which, I tried to compare their mole ratios before forming an equation. But it seems like the mole ratio don't fit well into the equation.

No. of moles of S2Cl2 and sulfur are 7.396X10^-3mol and 0.1121 mol respectively

thanks

qdtimes2 SG

lol ur careless for no.of moles of sulphur.. it shld be 0.01121

UltimaOnline SG

'O' & 'A' Level Qns.

Qn 1.
When 1.01g sample of potassium nitrate(V) is heated above its melting point, oxygen gas is evolved. The mass of the sample decreases by 0.16g. Construct a balanced equation for this decomposition reaction, name the residue and (for 'A' level students) draw its structural formula.

Q2.

Sulfur and chlorine can react together to form disulfur dichloride. When 1.00g of disulfur dichloride was reacted with water, 0.36g of a yellow precipitate of sulfur was formed together with a solution containing a mixture of sulfuric(IV) acid (a.k.a. sulfurous acid), and hydrochloric acid. Given that the most common isotope of sulfur is S₈, use the above data to deduce the balanced equation for the reaction between disulfur dichloride and water. (For 'A' level students) draw the structural formulae of disulfur dichloride and sulfuric(IV) acid.

Solutions (partial).

Qn1. Since 1 mole of potassium nitrate(V) decomposes to give 0.5 mole of oxygen gas, the residue is potassium nitrate(III) {stock name} or potassium nitrite {latin name}.

For the nitrate(III) ion (aka nitrite ion), uninegative formal charge on a singly bonded O atom; central N atom has 1 lone pair, 3 bond pairs; electron geometry tetrahedral, ionic geometry trigonal pyramidal.

Qn2. Since 1 mole of disulfur dichloride undergoes hydrolysis to give 1.5 moles of S(s), or 1.5/8 moles of S8(s), the coefficients of the balanced equation are : 2, 3, 1, 4, 3/8

For disulfur dichloride, the 2 central S atoms have 2 lone pairs and 2 bond pairs; electron geometry tetrahedral, molecular geometry v-shape.

For sulfuric(IV) acid {stock name} or sulfurous acid {latin name}, the central S atom has 1 lone pair, 4 bond pairs (S can expand its octet using its vacant and energetically accessible 3d orbitals); electron geometry tetrahedral, molecular geometry trigonal pyramidal.