戇戇居士

[匿名]

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2017-12-11 2:27 pm

HELP GUYS!!?

[匿名]

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2017-12-11 11:40 am

CHEM HELP NEEDED?

[匿名]

回覆: 1

2017-12-11 4:52 am

Out of the following, a 32g sample of oxygen, O2, gas is equal to:?

[匿名]

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2017-12-11 4:29 am

Which of the following contains the least number of atoms?

[匿名]

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2017-12-11 3:45 am

please help?

[匿名]

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2017-12-11 2:45 am

need some help please?

[匿名]

回覆: 2

2017-12-11 2:47 am

please explain this to me?

[匿名]

回覆: 1

2017-12-11 1:09 am

Chemistry HW question help!?

[匿名]

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2017-12-11 12:48 am

What is the edge length of a face-centered cubic unit cell made up of atoms having a radius of 139 pm?

[匿名]

回覆: 11

2017-12-10 8:39 pm

Need Help!!!!!!!!!!!!!?

[匿名]

回覆: 1

2017-12-10 5:23 pm

I need help for this one. explain if you could thank you?

[匿名]

回覆: 1

2017-12-10 9:19 am

what is the molecular geometry surrounding the nitrogen atom in nf3?

[匿名]

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2017-12-08 5:28 pm

Why can not a tertiary alkyl halide be used in the reaction of making an amine from an alkyl halide with azide?

[匿名]

回覆: 2

2017-12-08 5:40 pm

Is benzamide polar or non polar?

[匿名]

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2017-12-08 12:59 pm

need help on physics?

[匿名]

回覆: 1

2017-12-08 4:00 pm

this reaction in house temperature happend: 2SO3----->2SO2+O2 :delta(H)=+19.8 Is delta(G) negative? Why?

[匿名]

回覆: 1

2017-12-08 2:07 pm

Please help?

[匿名]

回覆: 2

2017-12-08 12:34 pm

Trigonometry help?

[匿名]

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2017-12-08 12:42 pm

what is the molarity (moles per liter) of a solution prepared by dissolving 320.g of NaOH [molar mass 40.0g/mol] in enough water to =800ml?

[匿名]

回覆: 1

2017-12-08 12:46 pm

What is [H3O+] for a buffer solution that is 0.200 M in acid and 0.500 M in the corresponding salt, if the weak acid's Ka = 5.50 × 10−7?

[匿名]

回覆: 1

2017-12-07 6:47 pm

solubility product of AgCl is 1.77 * (10^ -9) in 25 degrees C. Calculate the solubility of Ag+ ion in 0.1M NaCl solution!?

[匿名]

回覆: 3

2017-11-29 3:38 pm

chemistry redox reaction help?

[匿名]

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2017-11-29 3:58 pm

Balancing Redox acid?

[匿名]

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2017-11-29 3:03 pm

Need help with limiting reactant problems in chemistry?

[匿名]

回覆: 1

2017-11-29 2:30 pm

What is the pH of an aqueous solution of 2.09×10-3 M hydroiodic acid?

[匿名]

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2017-11-29 9:48 am

A generic salt, AB2, has a molar mass of 249 g/mol and a solubility of 1.10 g/L at 25 °C. What is the Ksp of this salt at 25 °C?

[匿名]

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2017-11-29 9:35 am

Determine the number of moles present in 8.39 x 1024 molecules of fluorine gas (F2)?

[匿名]

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2017-11-29 8:47 am

Suppose 1.25 g of sodium peroxide is added to a large excess of water. What mass of oxygen gas will be produced?

[匿名]

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2017-11-28 11:38 pm

Identify the number of electron groups around a molecule with a tetrahedral shape.?

[匿名]

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2017-11-28 11:09 pm

A gas fire with a yellow coloured flame is dangerous because ..?

[匿名]

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2017-11-28 7:19 pm

chemistry back titration question?

[匿名]

回覆: 3

2017-11-28 10:38 pm

AS LEVEL CHEMISTRY please help . I have an answer to my question but I don't know if its correct?

[匿名]

回覆: 2

2017-11-27 8:28 am

Chemistry Density Question (Any help appreciated, thanks!)?

[匿名]

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2017-11-27 7:51 am

AP Chemistry pH buffer question?? Help!?

[匿名]

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2017-11-27 8:09 am

The empirical formula of a compound is NO2. Its molecular mass is 46amu. What is the molecular formula of the compound?

[匿名]

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2017-11-27 7:04 am

How long would it take (min) for argon-44 to decrease from 96.0 to 12.0mg? Ar-44 Pb-196 K-44 Indium-117?

[匿名]

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2017-11-23 12:21 am

Chemistry help!!?

[匿名]

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2017-11-22 10:37 am

Chemistry help!?

[匿名]

回覆: 2

2017-11-22 2:00 pm

PLEASE HELP...STUCK WITH THIS PORTION?

[匿名]

回覆: 1

2017-11-22 2:01 pm

PLEASE HELP...STUCK ON THIS PORTION?

[匿名]

回覆: 2

2017-11-22 2:01 pm

STUCK ON THESE TWO AS WELL?

[匿名]

回覆: 1

2017-11-22 12:15 am

Silicon metal (Si) reacts with nitrogen gas (N2) to give silicon nitride (Si3N4) based on the following balanced reaction: 3 Si + 2 N2 -->?

[匿名]

回覆: 4

2017-11-21 11:54 pm

A certain isotope decays from 80 grams to 2.5 grams in 34 days. What is the half life of this isotope?

[匿名]

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2017-11-21 10:56 pm

mastering chem?

[匿名]

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2017-11-21 9:58 pm

mastering chemistry?

[匿名]

回覆: 2

2017-11-21 9:06 pm

CHEMISTRY?

[匿名]

回覆: 1

2017-11-21 12:55 pm

Calculate the wavelength (in nanometers) of a H atom (mass = 1.674 × 10−27 kg) moving at 3.75 × 102 cm/s.?

[匿名]

回覆: 1

2017-11-21 10:57 am

Redox Reaction Balanced Equation?

[匿名]

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2017-11-21 12:55 pm

What is the de Broglie wavelength, in cm, of a 12.4−g hummingbird flying at 1.20 × 102 mph? (1 mile = 1.61 km.)?

[匿名]

回覆: 1

2017-11-21 12:56 pm

Indicate the total number of: (a) p electrons in N (Z = 7) (b) s electrons in Si (Z = 14) (c) 3d electrons in S (Z = 16)?