mod 8

mod 8 :)

PSAAA

1. Please don't ever hesitate to email or text me if you need help! Me and the other peer leaders are always here for you, take advantage!

2. What are some things that you could do to get a better grade for the next exam?

3. Do you feel comfortable talking to Dr. Saupe?

How do you approach a problem?

First, look at what the problem is asking for! Write it down, circle it, highlight

Look at what the question provides

Determine what equation you will need to solve this problem

Open Ended

What do you know about work? What about Calorimetry?

WORK :0

w = -P delta V

What does this mean?

Break it down,

p = atm

delta v = in liters!

Work is used to calculate the amount of energy of the system

1L x atm = 101.325 J

Multiple Choice

Doing work ON the system means that work is greater than 0

• True

• False

Think about the relationship

If the final volume is greater than initial volume, Delta V is pos

If initial volume is greater than final, delta V is neg.

Lets get the concept down.

Multiple Choice

In Delta V, if VF is 10 and VI is 5, is delta V positive or negative?

Is work done ON the system or BY the system?

• Pos

  On the systen

• Neg

  On the system

• Pos

  By the system

• Neg

  By the system

Multiple Choice

If the initial volume is greater than the final volume, work is done BY the system

• True

• False

Work in groups and try to figure it out!!

What is the question asking for?

What does it give?

use pg 204 to help

A gas in a piston with initial volume of 12.3 L is heated from 24 C to 300 C, and the piston expands against a constant pressure of 1.30 atm. Find the work done (in J) by the system.

​What is the equation for work?

EXAMPLE

CALORIMETRY

q= ms delta T (can be in c or k)

q= C delta T

qA= -qB

q= must be in joules or kilojoules

m= mass in grams

s= specific heat

c= heat cap

​