What volume of a 1.00 m stock solution of glucose must be used to make 500.0 ml of a 1.75 ✕ 10–2 m glucose solution in water? (a) 1.75 ml, (b) 8.75 ml, (c) 48.6 ml, (d) 57.1 ml, (e) 28,570 ml?

Answer : The correct option is, (b) 8.75 ml

Solution :

According to the dilution law,

where,

= molarity of stock solution = 1.00 M

= volume of stock solution = ?

= molarity of glucose solution =

= volume of glucose solution = 500 ml

Now put all the given values in the above law, we get the volume of stock solution.

Therefore, the volume of 1.00 M stock solution required volume is, 8.75 ml

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.