pick one i got alot

Given a weak acid with a pKa of 5.5:

1) In what pH range would this acid be an effective buffer?

2) In a 0.18M solution at pH 8.0,what fraction would be in the conjugate base form?

3) At pH 8.5, what fraction would be in the conjugate base form?

ok i need to LEARN how to do this i have 20 more that i want to work on my own, can anyone walk me through this step by step?

1) i believe 4.5 to 6.5, add one substrate one as a general rule

2 ) a bead with a mass of .05 kg is released from rest from a height of 60 cm above the bottom of a loop with a radius of 20 cm

a) what is the velocity at the top of the loop neglecting friction

b) calculate the normal force at this point on the bead from the track and state the direction of that force.

c) if the bead actually arrives at the top of the loop with a velocity of 1.5 m/s how much energy was"lost" in overcoming friction

1. A ball with a mass of .5 kg is tossed straight up at a speed of 25 m/s

a) how far will the ball go without air resistance?

b) if its actual height was 22 m how much energy was lost to frictional forces

c) what was the average force due to air resistance.

For the hydrolysis of ATP to ADP + inorganic phosphate, the free energy change is -7.3 kcal/mol under standard conditions (1 M concentration of both reactants and products). In the cellular environment, however, the free energy change is about -13 kcal/mol. What can we conclude about the free energy change for the formation of ATP from ADP and inorganic phospahte under cellular conditions?

A It is +7.3 kcal/mol.

B It is less than +7.3 kcal/mol.

C It is greater than +13 kcal/mol.

D It is about +13 kcal/mol.

E The information given is insufficient to deduce the free energy change.

i am confused. what i can figure that under cellular condition the process produces almost 80 percent more energy, therefore the cellular conditions vary from the standard conditions.

The binding of a compound to an enzyme is observed to slow down or stop the rate of the reaction catalyzed by the enzyme. Increasing the substrate concentration reduces the inhibitory effects of this compound. Which of the following could account for this observation?

a The compound is a competitive inhibitor.

b The compound reduces disulfide bonds, causing the enzyme molecules to partially unfold.

c The compound causes a cofactor to be lost from the enzyme.

d The compound is a negative allosteric regulator.

e The compound forms a covalent bond with one of the amino acid residues needed for enzyme activity.

In order to attach a particular amino acid to the tRNA molecule that will transport it, an enzyme, an aminoacyl-tRNA synthetase, is required, along with ATP. Initially, the enzyme has an active site for ATP and another for the amino acid, but it is not able to attach the tRNA. What must occur in order for the final attachment to occur?

A The ATP must first have to attach to the tRNA.

B The ATP must be hydrolyzed to allow the amino acid to bind to the synthetase.

C The binding of the first two molecules must cause a 3-D change that opens another active site on the enzyme.

D The tRNA molecule must have to alter its shape in order to be able to fit into the active site with the other two molecules.

E The 3' end of the tRNA must have to be cleaved before it can have an attached amino acid.

Protein kinases are enzymes that transfer the terminal phosphate from ATP to an amino acid residue on the target protein. Many are located on the plasma membrane as integral membrane proteins or peripheral membrane proteins. What purpose may be served by their plasma membrane localization?

1 Membrane localization lowers the activation energy of the phosphorylation reaction.

2 They can more readily encounter and phosphorylate other membrane proteins.

3 They require phospholipids as a cofactor.

4 They flip back and forth across the membrane to access target proteins on either side.

5 ATP is more abundant near the plasma membrane.

Do some of the questions asked in this forum about guns scare you that this person might actually own a gun and be that clueless and uninformed.

what percentage of people asking gun questions here probably shouldn't be allowed to have a dull butter knife let alone a gun.

some of the questions seem like they are gonna be the intro in a darwin award,

thanks for answering i am gonna go get prepped to take my test so i can go get my new air soft with poison exploding depleted plutonium bb s out of layaway

also for people asking gun value question could you perhaps be a bit more vague, here is a list of things that will make answering your question easier and more accurate. DO NOT PUT THE WHOLE SERIAL NUMBER IN, leave the last two or three as X's , example 123873XXX

1. MODEL NUMBER i can not stress this enough, a model number makes this about a million times easier

2. CALIBER oddly enough winchesters model 94 was made in about 7 calibers, some of the rare calibers are worth to or three times the common calibers

3. BARREL LENGTH a 2.5 inch colt python is quite a bit more rare than the common 6 in barrel

4. FINISH AND CONDITION, yeah different finishes are more rare and its condition affects value

5. any other details, examples, octagon barrel, target sights, saddle ring, large hand loop, anything stamped on the Receiver or barrel, hell provide a brief disciption, armory marks, configuration,