Chemistry

Help with Chem Questions

1) Write net ionic equations for the following precipitation reactions. a) 2KI(aq) + Pb(NO3)2(aq) --> PbI2(s) + 2KNO3(aq) b) Ba(NO3)2(aq) + Na2SO4(aq) --> BaSO4(s) + 2NaNO3(aq) 2) Consider the follo

Another Chemistry Question

At a dosage of 20 micro/kg body weight, (i) how many milligrams of dosage should a 78kg patient receive? (ii) how many milligrams of dosage should a 160lb patient receive? ( 1kg=2.2046lb)-(1) 78kg = 7

Chemistry help please :)

a particular reaction is found to have the following rate law R=k[a][b]^2 how is the rate affected by each of the following changes?a. the initial concentration of A is cut in halfb. The initial conce

Which among the given acids is the strongest

a) Cl-CH2-COOH b) Br-CH2COOH c) O2N-CH2COOH d) NC-CH2COOH-2-Nitroethanoic acid is the strongest out of these. Remember that -NO2 group has the maximum -I effect ie ability to withdraw electrons toward

What is the molarity of a solution that was prepared by diluting 24.0 mL of 8.0 M NaOH to a total vol.of 500mL

using the dilution formula: C1V1 = C2V2 (8.0M) (24.0 ml) = (C2) (500ml) C2 = 0.384 Molar which rounded to 2 sig figs would be 0.38 Molar NaOH

I need help with gas laws for chem. how do you do this problem

X[ 3.45 moles of hydrogen gas are collected at 1.05 atm and 300.0 K. the sample is cooled to 145.0 K. what is the new pressure? a 5.0L volume of gas has a pressure of 1.4 atm. what pressure will this

What do you get for you answer to this chemistry problem

he says the answer is 490 ml but im getting 50 L... what volume of water must be added to 10.0 mL of 5.0 M HCL to make a solution of .10M HCL?-your friend is right, you would use the formula M1 (initi

Whats the ph of this buffer solution

1.what is the ph for each of these i)A 0.0100 M aqueous solution of acetic acid [pKa 4.77].ii)A 0.0100 M aqueous solution of ammonia [pKa 9.25, pKw14.0]. 2.Determine the pH of a buffer solution made

What is the charge on the anode of an electrolytic cell? of a voltaic cell

the charge on the anode of an electrolytic cell is positive http://www.google.com/imgres?imgurl=http… ======================================… the charge on the anode of a voltaic cell is negative

An atom of Ca undergoes oxidation to Ca +2, the number of neutrons in its nucleus ...

1. decreases 2. increases 3. remains the same ????-3.Remains the same. As does the number of protons. The only thing that changes in an oxidation or reduction reaction is the number of electrons.-3

Help with chemistry homework

Use Xs and Os to draw three different samples: and element, a compound, a mixture. Thanks for your help!-X = an element O = another element or the same one XO = a compound of element X and element

When finding the molarity of a diluted concentration, is there ever a time you can't use the M1V1=M2V2 formula

Interesting question. There might be, but I think its going to be in some very esoteric application. From my high school time to now (extending over 40 years), I have not come across a situation wher

Mass Percentage of an unknown used in acid-base titration

Aqueous K3 contains 5.0g dm-3 mixture NaOH+KOH. Aqueous K4 contains 0.05 mol dm-3 H2 SO4. It was found that 25cm3 K4 is exactly neutralized by 23.80cm3 K3. a. Calculate the molarity of OH- ions in d

A sample gas has an initial volume of 25L and an initial pressure of 3.5atm. If the pressure changes to 1.3atm

What is the new volume?-P1V1 = P2V2 3.5 atm (25 L) = 1.3 atm (V2) 67.3 L = V2

Giant covalent structures

I have an assignment about bonding and ive been asked to include information on giant covalent structures but I just dont understand.. can anyone help me?-Giant covalent structures are not molecules b