An edta solution was prepared by dissolving 3.7015g of disodium acid dihydrate (mw=372.3) in enough water to make 100ml of solution a .01732g portion of a solid sample which contained copper(ii) was dissolved in 100 ml of a ph 2 bufer solution. the endpoint of the titration was 9.98ml. calculate the percent copper in the solid sample.

The percent copper in the solid sample is 27.5 %

Explanation:

Step 1: The balanced equation

Cu + EDTA → Cu-EDTAcomplex

Step 2: Given data

mass of disodium acid dihydrate (EDTA) = 3.7015g

Molar mass of EDTA = 372.3 g/mol

volume of the solution = 100 mL

mass of the copper(II) containing sample = 0.01732g

pH of the solution = 2

The endpoint of the titration = 9.98mL

Step 3: Calculate number of moles of EDTA

Moles = mass of EDTA / Molar mass

moles = 3.7015g /372.3g/mol

moles = 0.00994 moles

Step 4: Calculate molarity of EDTA

Molarity of EDTA = number of moles / volume of EDTA

Molarity = 0.00994 moles / 0.1 L = 0.0994 M

Step 5: Calculate moles of Cu

moles = molarity * volume

moles = 0.0994 M * 0.00998L = 0.000992 moles

Step 6: Calculate mass of Cu

Mass of Cu = moles of Cu * Molar mass of Cu

mass of Cu = 0.000992 moles * 63.546 g/mol

mass of Cu = 0.063 grams

Step 7: Calculate the procent copper

(0.01732 grams/ 0.063 grams) = 27.5%

catya that's not even a b or c

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.