Distinguish between the following:   a) heterogeneous and homogeneous   b) solute and solvent   c) pure substance and mechanical mixture   d) ionic and covalent binding   e) density and mass  f) law of conservation of mass, law of definite proportions, and law of multiple proportions

Hello, Tuilps2411!!

A) Heterogenous usually is referred as a mixture, whereas homogeneous is referred to as a solution. In a homogeneous solution, everything is uniform, which means everything works together and there is nothing that will happen since there is only one phase of matter in a homogeneous solution (air, vinegar). As for a heterogeneous mixture, things are not uniform and you can pick out things that are different/same (ice cubes out of a drink).

B) Whenever you mix things together, one will be a solute and a solvent. For a solute, it will be the one that is being dissolved (sugar). The other will be the solvent, which the one who does the dissolving (water).

C) In a pure substance, there is only one particle, whereas a mechanical mixture has two. You cannot see the particles in the pure substance, but you can in the mechanical mixture. You cannot separate a pure substance (gold), but you can in a mechanical mixture (pens in rice).

D) In an ionic bond, there is a bond there because the atoms are attracted due to their opposite charges (cation who has positive charge and anion which has a negative charge). Usually happen between a metallic and non-metallic atom. As for covalent bonds, they share one of multiple different atoms. They usually happen between two non-metallic atoms.

E) Density determines how much density there is in a certain thing. It will always be D = M/V. Density = Mass/Volume. As for mass, it determines how heavy (weight) things are.

F) Law of Conservation of Mass tells how the mass of the products in the reaction must equal the mass of the reactants. Law of Definite Proportions says that a compound always has its elements in a certain ratio by mass and does not depend on method of preparation. For Law of Multiple Proportions, it says that two elements bind with each other to create more than one compound, they are usually found in small whole number ratios whenever the one element is combined with a fixed weight.

I hope I helped :)

when 25.0 ml of 0.700 mol/l naoh was mixed in a calorimeter with 25.0 ml of 0.700 mol/l hcl, both initially at 20.0 °c, the temperature increased to 22.1 °c. the heat capacity of the calorimeter is 279 j/°c.

the equation for the reaction is:

naoh + hcl → nacl + h₂o

moles of hcl = 0.0250 l hcl ×

0.700

mol hcl

1 l hcl = 0.0175 mol hcl

volume of solution = (25.0 + 25.0) ml = 50.0 ml

mass of solution = 50.0 ml soln ×

1.00

ml soln

= 50.0 g soln

δt=t2-t1

= (22.1 – 20.0) °c = 2.1 °c

the heats involved are

heat from neutralization + heat to warm solution + heat to warm calorimeter = 0

q1+q2+q3=0

nδh+mcδt+cδt=0

0.0175 mol ×

δh

+ 50.0 g × 4.184 j·g⁻¹°c⁻¹ × 2.1 °c + 279 j°c⁻¹ × 2.1 °c = 0

0.0175 mol ×

δh

+ 439.32 j + 585.9 j = 0

0.0175 mol ×

δh

= -1025.22 j

δh=1025.22j0.0175 mol= -58 600 j/mol = -58.6 kj/mol