Chemistry - May 2007

Na2HPO4
Na3PO4

2007-05-30 10:19:24 · 1 answers · asked by Anonymous

Scientists studying proteins express mass in terms of daltons, where one dalton = one atomic weight unit (amu). A kilodalton (kd) is 1,000 daltons. How many amino acid residues would you expect in a protein that has a mass of 50 kd?

Average molar mass of amino acids = 135g/mole

2007-05-30 09:59:58 · 3 answers · asked by Anonymous

Which of these does the single oxidation of a secondary alcohol forms:

1) no reaction.
2) an aldehyde.
3) a ketone.
4) an ester.
5) a carboxylic acid.

2007-05-30 09:53:32 · 5 answers · asked by theweirdguy1 2

Name each molecule: NH2Cl, Cl2O, AsH5, AlH3, CCl2F2, O3(ozone). Which of these molecules are polar? For the polar molecules, label the electronegativity of each atom and show where the partial charges reside. Thanks so much!

2007-05-30 09:47:53 · 1 answers · asked by razac24 1

What is the difference between picardin and deet? They are both used in mosquito repellent but I am not sure which works better and if one is bad for your skin to absorb?

2007-05-30 09:25:39 · 1 answers · asked by Anonymous

Discuss the deleterious effects of ice formation in foods.

2007-05-30 08:26:54 · 1 answers · asked by Anonymous

The waste water is produced from refining crude oil,the water goes to a channel after treatment to reduce the amount of the harmful materials but the phenol exceeds the specification.

2007-05-30 08:04:28 · 1 answers · asked by Eman S 1

How much energy is required to change the temperature of 21.5 g Cu from 27.0 °C to 88.1 °C? The specific heat capacity of copper is 0.385 J/g·K.

a.223 J
b.506 J
c.729 J
d.641 J
e.3.41 × 103 J

2007-05-30 08:03:57 · 2 answers · asked by Anonymous

Which one of the following statements is INCORRECT?

a.The SI unit of specific heat capacity is joules per gram per Kelvin.

b.The specific heat capacity has a positive value for liquids and a negative value for gases.

c.In an exothermic process heat is transferred from the system to the surroundings.

d.When heat is transferred from the system to the surroundings, q is negative.

e.The greater the heat capacity of an object, the more thermal energy it can store.

2007-05-30 08:03:20 · 3 answers · asked by Anonymous

Which molecule in the reaction below undergoes oxidation?

2 C2H2(g) + 5 O2(g) → 4 CO2(g) + 2 H2O(g)

a.H2O
b.C2H2
c.O2
d.C2H2 and O2
e.CO2

2007-05-30 07:57:03 · 3 answers · asked by Anonymous

Which of the following chemical equations is an acid-base reaction?

a.2 HCl(aq) + Zn(s) → H2(g) + ZnCl2(aq)
b.Ba(OH)2(aq) + Na2SO4(aq) → BaSO4(s) + 2 NaOH(aq)
c.2 NaOH(aq) + CuCl2(aq) → Cu(OH)2(s) + 2 NaCl(aq)
d.HCl(aq) + AgNO3(aq) → AgCl(s) + HNO3(aq)
e.HCl(aq) + NH3(aq) → NH4Cl(aq)

2007-05-30 07:54:54 · 5 answers · asked by Anonymous

What are the spectator ions in the reaction between aqueous perchloric acid and aqueous potassium hydroxide?

a.K+ and OH-
b.K+ and ClO4-
c.H+ and OH-
d.H+, ClO4-, K+, and OH-
e.H+ and ClO4-

2007-05-30 07:51:55 · 2 answers · asked by Anonymous

What is the oxidation number of each atom in sodium perbromate, NaBrO4?

a.Na = +1, Br = -1, O = 0
b.Na = +1, Br = -1, O = -2
c.Na = -1, Br = -1, O = +2
d.Na = +1, Br = +7, O = -2
e.Na = +1, Br = +1, O = -2

2007-05-30 07:51:00 · 3 answers · asked by Anonymous

A precipitate will form when aqueous AgNO3 is added to an aqueous solution of ____.

a.KNO3
b.Ca(ClO4)2
c.KI
d.NaNO3
e.Cu(NO3)2

2007-05-30 07:50:20 · 3 answers · asked by Anonymous

2007-05-30 07:49:58 · 1 answers · asked by BJ416 1

All of the following are oxidation-reduction reactions EXCEPT

a.2 NaBr(aq) + F2(g) → 2 NaF(aq) + Br2(g)
b.H2(g) + Br2(g) → 2 HBr(g)
c.Ca(s) + 2 HCl(aq) → CaCl2(aq) + H2(g)
d.CaO(s) + H2O(λ) → Ca(OH)2(aq)
e.2 H2O(λ) → 2 H2(g) + O2(g)

2007-05-30 07:49:30 · 1 answers · asked by Anonymous

Which of the following compounds will be soluble in water: LiOH, Mg(OH)2, Cu(OH)2, and Fe(OH)3?

a.LiOH and Mg(OH)2
b.Mg(OH)2 and Cu(OH)2
c.LiOH, Mg(OH)2, and Fe(OH)3
d.Cu(OH)2 and Fe(OH)3
e.LiOH only

2007-05-30 07:46:00 · 1 answers · asked by Anonymous

One use of calcium oxide (lime) is in pollution control at coal-burning power plants. Which reaction below occurs in the smokestack of a power plant?

a.CaO(s) + SO3(g) → Ca(s) + SO2(g) + O2(g)
b.CaO(s) + SO3(g) → CaS(s) + 2 O2(g)
c.2 CaO(s) + C(s) → Ca2C(s) + O2(g)
d.CaO(s) + SO3(g) → CaSO4(s)
e.CaO(s) + C(s) → Ca(s) + CO(g)

2007-05-30 07:45:06 · 2 answers · asked by Anonymous

A precipitate will form when aqueous iron(II) bromide is added to ____.

a.Na2SO4
b.Ba(OH)2
c.NaCl
d.Cu(NO3)2
e.KI

2007-05-30 07:44:23 · 3 answers · asked by Anonymous

Which one of the following compounds is a weak electrolyte when dissolved in water?

a.acetic acid (CH3CO2H)
b.sodium acetate (NaCH3CO2)
c.sodium hydroxide (NaOH)
d.calcium chloride (CaCl2)
e.glucose (C6H12O6)

2007-05-30 07:34:30 · 2 answers · asked by Anonymous

The question says: Find the gram equivalent masses for each of the following acids and bases.
a. H3PO4

b.Mg(OH)3

c.HF

How do I do this?

Thank You!!!

2007-05-30 07:25:25 · 6 answers · asked by ♥chloe♥ 2

Nitric oxide is made from the oxidation of ammonia. How many moles of nitric oxide can be made from the reaction of 3.80 mol NH3 with 5.15 mol O2?

4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(g)

a.4.12 mol
b.6.44 mol
c.5.15 mol
d.8.95 mol
e.3.80 mol

2007-05-30 07:14:46 · 2 answers · asked by Anonymous

What mass of oxygen is consumed by the complete combustion of 23.0 grams of ethylene?

C2H4(g) + 3 O2(g) → 2 CO2(g) + 2 H2O(g)

a.8.75 g
b.69.0 g
c.78.7 g
d.26.2 g
e.60.5 g

is it answer a?
thanks

2007-05-30 07:03:46 · 2 answers · asked by Anonymous

1.what is the structure of the trans-3-hexene molecule.(how do you draw it?)

2.assuming there is enough energy to initiate a reaction with trans-3-hexene what is the structure and the name of the hydration product.

3. When exposed to air the product in question 2 becomes oxidized. what is the structure and name of this oxidation product?

4. Can the product in question 3 undergo further oxidation? explain please.

5. order the 3 molecules trans-3-hexene,the products in part 2 and 3 from the lowest to the highest boiling point.

when answering make sure you are positive with your answer please and thank you to all who answer

2007-05-30 07:03:08 · 3 answers · asked by MEB 2

2007-05-30 06:56:26 · 1 answers · asked by Anonymous

1.what is the structure of the trans-3-hexane molecule.(how do you draw it?)

2.assuming there is enough energy to initiate a reaction with trans-3-hexane what is the structure and the name of the hydration product.

3. When exposed to air the product in question 2 becomes oxidized. what is the structure and name of this oxidation product?

4. Can the product in question 3 undergo further oxidation? explain please.

5. order the 3 molecules trans-3-hexane,the products in part 2 and 3 from the lowest to the highest boiling point.

when answering make sure you are positive with your answer please and thank you to all who answer!

2007-05-30 06:16:07 · 1 answers · asked by MEB 2

For salts that form acidic or basic solutions , write a balanced equation for the reaction.
1. NH4BR
2. KNO2
3.Mg(NO3)2
4. BaF2
5.K2S

2007-05-30 06:06:57 · 3 answers · asked by mweber126 1

1. write and Equation that shows this buffer neutralizes small amounts of acid.
2. write an equation that shows how this buffer neutralizes small amounts of base.

2007-05-30 05:53:45 · 1 answers · asked by mweber126 1

1: This ion is in every acid
OH-
H-
H+
O2-


2: This ion is in every base
OH-
H-
H+
O2-


3: Mixing an acid and a base in water most often creates:
more acid
water only
salt
more base


4: Salts normally have a PH of:
7
2
14
10

2007-05-30 05:48:24 · 4 answers · asked by !it is me! 2

2007-05-30 05:45:30 · 5 answers · asked by Brightbulb 1