DRAP - Carlos A

8/7/2019 DRAP - Carlos A.

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DRAP IN CHEMISTRY

Carlos Antonio C. Albornoz

III - Masinop

QUESTIONS FROM GROUP 1

1.Why liquids are different from solids?

Liquids have molecules that are lose and bouncy while

solids have molecules hard and packed together. Liquids take the

shape of whatever it is in while solids have a definite shape of it'sown. solids are something that you can feel and hold while liquids

are something you could feel but never actually hold it cause the

molecules don't stick together it just bounces around.

2. Why are solids and liquids important?

Solids & Liquids are important because our necessities to

live like water, food etc. are Solids & Liquids. Without them, we

would not exist.

3. How does physical equilibrium in liquid occur?

Physical Equilibrium in liquids do not involve changes to its

chemical properties. For example, the equilibrium of water vapor

with liquid water in a half-full bottle. The water moleclues are still

the same even though it became vapor. And in a physical

equilibrium, an equal number of liquids condense during the

same time interval. (i.e., the rates are equal)

4. Compare & Contrast rate of evaporation and

boiling point.

Evaporation -The process by which any substance isconverted from a liquid state into, and carried off in, vapor; as,


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the evaporation of water, of ether, of camphor.

Boiling point The boiling point of an element or a

substance is the temperature at which a liquid boils and turns to

vapor.


1. The titanium alloy measures 45.0g is heated to

95.900C and then put in liquid where it cools to

18.440C. The amount of heat lost by the alloy is

-870J. What is the specific heat of the alloy?

G:T2-18.440C m-40.60g

q- 870 J T1- 95.900C

R: Specific heat (SF)

E: Specific heat= q .

m T

S: SH= -870 J

(45.60)(95.900C-18.440C)

A: SH= 0.246 Jg-10C-1

2. The heat capacity of a cup is 106 J0C-1, when the cup

is filled with hot water, the temperature of the cup

increases from 19.30C to 66.80C. How much heat

does the cup gain?


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G:T1 - 19.30C C -106 J0C-1

T2 - 66.8

R: q

E:q = c t

S: q=(106 J0C-1) (66.8-19.30C)

A: q= 5035 J

3. A cylinder contains 26.3 gN2

at 25.00C. The gas is

heated to a temperature of 88.4 0C. What is the

amount of energy added to the gas to cause the

temperature change?

G: specific heat = 1.0376 J0C-1 T1 - 25.00C

T2 - 88.4 0C m - 26.3g

R: q

E: q = m(specific heat) t

S: q=(26.3g)( 1.0376 J0C-1)( 88.4 0C-25.00C)

A: 1730.11 J


1.What is the tail end of the cold front?

A cold front is the transition zone where a cold air mass is

replacing a warmer air mass. The tail end of a front is the back edge of


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that frontal boundary, not the back of the air mass itself. Cooler air

that wedges below the warm air mass causes that air to rise. This

causes precipitation as the front passes.


1. 64 of CH3OH dissolved in 4Kg of H2O. Find M and m.

G: 64g of CH3OH= 2.21 moles

4Kg of H2O

R: m (molality)

E: m = n .

m solvent

S: m = 2.21mole


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4kg

A: 0.55 molal


1. 13.05% sugar solution (C6H6O12)

G: 13.05% C6H6O12

R: Molar fraction

E: mole fraction =mole(solute)/mole solute+ mole

solvent

S: 13.05% C6H6O12 86.95% water

C=612=72

H=61=6

0=1216=192

=270 13.06/270 = .048 mole C6H6O12

H= 12=2

0=116=16

=18 86.95/18 = 4.83 mole water

Mole fraction = 0.048/ 0.048+ 4.83 ===MF=0.0098

A: MF=0.0098

2.80 % NaOH solution


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G: 80% NaOH solution

R: molar fraction

E: mole fraction = mole(solute)/mole solute+ mole

solvent

S: 80% NaOH solution

20% water

NaOH=Na=123=23

O=116=16

H= 11=1=40 80/40==2moles NaOH

Water= H= 12=2

0=116=16

=18 20/18 = 1.1 mole water

Mole fraction= 2/2+1.1 =0.65

A: mole fraction = 0.65

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DRAP - Carlos A