What is the temperature shown on the thermometer below?

If the outside of your flask is not dry when the first mass determination is made and it is dried for the second mass determinat

svlad2 [7]

Answer:

You'll experience a grater deviation

Explanation:

<em>You'll experience a greater deviation in your measurements, meaning your measures will have a bigger difference between them, and the greater these deviations the less accurate will be the measuring.</em> This happens mainly because you're not replicating the measurement with the exact same conditions, in one of them you'll have an extra mass from the water.

I hope you find this information useful and interesting! Good luck!

8 0

3 years ago

Assuming constant pressure, rank these reactions from most energy released by the system to most energy absorbed by the system,

givi [52]

Answer: The order from the Most energy released to most Energy Absorbed Is given as 2---> 4--->,3-->---> 1

B)-61.9 kJ

Explanation:

The change in the internal energy of a system is positive if the reaction absorbs energy and negative if the reaction releases energy. For a system to cause an increase in volume, it must have very high energy built up to be released.

1. Surroundings get colder and the system decreases in volume. Here, the surrounding absorbs energy resulting in positive ΔE

2. Surroundings get hotter and the system expands in volume. Here energy is released causing the system to be negative

3. Surroundings get hotter and the system decreases in volume. Although there is a decreased volume, the system is negative because it releases energy

4. Surroundings get hotter and the system does not change in volume. System is negative because it releases energy even thgoygh there is no change in volume

Therefore the order from the Most energy released to most Energy Absorbed Is given as 2---> 4--->,3-->---> 1

b) Using

ΔE = q+ w from 1st law of thermodynamics

ΔE= ΔH - P ΔV

gIven

ΔH = -75.0KJ

volume= A change from 5.0L TO 2.0L = Final volume - initial volume = 2-5= -3.00L

P= 43.0atm

ΔE= ΔH - P ΔV

P ΔV = 43 atm x -3 = -129L.atm

We first convert L-atm to Joules.

1 L-atm = 101.325 Joules.

129L.atm = 129 x 101.325 = - 13071 J

to KJ becomes

13071/1000 = - 13.071KJ

Recall ΔE= ΔH - P ΔV and putting values

ΔE = -75.0 - (-13.071 KJ)= -75.0 kJ + 13.071 kJ = -61.9 kJ

8 0

3 years ago

a concentration solution of H2so4 is 59.4% by mass (m/m) and has a density of 1.83 g/mL. How many mL of the solution would be re

Blababa [14]

Answer: 41.5 mL

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n}{V_s}$

where,

n = moles of solute

$V_s$ = volume of solution in L

Given : 59.4 g of $H_2SO_4$ in 100 g of solution

moles of $H_2SO_4=\frac{\text {given mass}}{\text {molar mass}}=\frac{59.4g}{98g/mol}=0.61$

Volume of solution = $\frac{\text {mass of solution}}{\text {density of solution}}=\frac{100g}{1.83g/ml}=54.6ml$

Now put all the given values in the formula of molality, we get

$Molality=\frac{0.61\times 1000}{54.6ml}=11.2M$

To calculate the volume of acid, we use the equation given by neutralisation reaction:

$M_1V_1=M_2V_2$

where,

$M_1\text{ and }V_1$ are the molarity and volume of stock acid which is $H_2SO_4$

$M_2\text{ and }V_2$ are the molarity and volume of dilute acid which is $H_2SO_4$

We are given:

$M_1=11.2M\\V_1=mL\\M_2=0.30M\\V_2=1550mL$

Putting values in above equation, we get:

$11.2\times V_1=0.30\times 1550\\\\V_1=41.5mL$

Thus 41.5 mL of the solution would be required to prepare 1550 mL of a .30M solution of the acid

4 0

3 years ago

20 POINTS!!

Elza [17]

The answer is option number one

4 0

3 years ago

Read 2 more answers

In your discussion consider a SN2 reaction mechanism concept. Propose a modification of experimental procedure that would improv

Hitman42 [59]

Answer:

Here's what I get

Explanation:

You may have done a Williamson synthesis of guaifenesin by reacting guaiacol with 3-chloropropane-1,2-diol.

A. Mechanism

Step 1

NaOH converts guaiacol into a phenoxide ion.

Step 2

The phenoxide acts as the nucleophile in an SN2 reaction to displace the Cl from the alkyl halide.

B. Improve the yield

You probably carried out the reaction in ethanol solution — a polar protic solvent.

You might try doing the reaction in a polar aprotic solvent— perhaps DMSO.

A polar aprotic solvent does not hydrogen bond to nucleophiles, so they become stronger.

C. Another method of ether synthesis —dehydration of alcohols

Sulfuric acid catalyzes the conversion of primary alcohols to ethers.

This is also a nucleophilic displacement reaction.

Protonation of the OH converts it into a better leaving group.

Attack by a second molecule of alcohol forms the protonated ether.

A molecule of water then removes the proton.

6 0

3 years ago