戇戇居士

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2017-11-05 3:23 pm

Chemistry help?

[匿名]

回覆: 1

2017-11-05 11:00 am

How much energy is evolved when 2.75 mg of Cl (g) atoms adds electrons to give Cl- (g) ions? Electron affinity (Cl) = -349kJ/mol?

[匿名]

回覆: 2

2017-11-04 10:46 pm

Making CO from CO2 is a potential energy source. The value of Kp for the reaction is is 1.50 at 700.0°C. CO2​(g)+C(s)=2CO(g)?

[匿名]

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2017-11-04 11:22 am

Indicate concentration of each ion present in solution formed by mixing the following. 3.50 g of NaCl in 44.2 mL of 0.238 M CaCl2 solution?

[匿名]

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2017-11-03 11:01 am

The solubility of PbCrO4 in water at 25°C is measured to be ×1.710−4gL . Use this information to calculate Ksp for PbCrO4 .?

[匿名]

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2017-11-01 2:05 pm

Arrange the following atoms or ions in order of decreasing ionization energy: Sr2+, Se2-, Rb+, Br-?

[匿名]

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2017-11-01 8:41 am

CH3(C=O)CH3(g) + 4 O2(g) → 3 CO2(g) + 3 H2O(g) I need help determine the approximate enthalpy (in kj) please help?

[匿名]

回覆: 2

2017-11-01 9:33 am

Chem Question?

[匿名]

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2017-10-31 11:55 pm

A 100 g sample of each of the following metals is heated from 35°C to 45°C. Which metal absorbs the lowest amount of heat energy?

[匿名]

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2017-10-31 10:38 am

Calculate volume (liters) of 1.572 M KOH that must be added to a 0.112 L solution of 9.80 g of (H3Glu Cl–, MW = 183.59 g/mol) for pH 10.35?

[匿名]

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2017-10-31 1:16 pm

Chem question?

[匿名]

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2017-10-31 10:43 am

How many moles of CO2 gas are produced?

[匿名]

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2017-10-31 1:28 am

3.00×10−3 mol of HBr are dissolved in water to make 16.0 L of solution.What is the concentration of hydroxide ions, [OH−] in this solution?

[匿名]

回覆: 1

2017-10-31 1:28 am

3.00×10−3 mol of HBr are dissolved in water to make 16.0 L of solution.What is the concentration of hydroxide ions, [OH−] in this solution?

[匿名]

回覆: 1

2017-10-31 1:28 am

3.00×10−3 mol of HBr are dissolved in water to make 16.0 L of solution.What is the concentration of hydroxide ions, [OH−] in this solution?

[匿名]

回覆: 2

2017-10-31 1:28 am

3.00×10−3 mol of HBr are dissolved in water to make 16.0 L of solution.What is the concentration of hydroxide ions, [OH−] in this solution?

[匿名]

回覆: 1

2017-10-30 12:26 pm

HClO is a weak acid (Ka = 4.0 × 10–8) and the salt NaClO acts as a weak base. What is the pH of a solution with 0.024 M in NaClO at 25 °C?

[匿名]

回覆: 5

2017-10-30 3:02 pm

How do I factor x^3-9x-440=0?

[匿名]

回覆: 2

2017-10-30 11:57 am

Name all of the alkene isomers, C6H12, that contain an unbranched chain and that have E/Z isomers.?

[匿名]

回覆: 2

2017-10-30 11:19 am

Draw the structure(s) of all of the alkene isomers, C6H12, that contain an unbranched chain and that have E/Z isomers.?

[匿名]

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2017-10-30 9:44 am

What mass of oxygen is needed for the complete combustion of 4.00×10−3 g of methane?

[匿名]

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2017-10-30 8:44 am

A sample of oxygen has a pressure of 500. kPa at 40.0∘C. What will be the temperature in Kelvin at a pressure of 630. kPa?

[匿名]

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2017-10-29 11:50 pm

I need help understand this chemistry problem!?

[匿名]

回覆: 2

2017-10-26 10:17 pm

50.00 mL of 0.0200 M MES (Ka = 5.37x 10^-7) is titrated with 0.1000 M NaOH. Determine which indicator is most appropriate for this titration?

[匿名]

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2017-10-25 1:35 pm

Calc. the pressure of dry O2 if the total pressure of O2 generated over water is measured to be 638 torr and the temp. 22C PH2O=19.8 torr?

[匿名]

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2017-10-25 10:48 am

CHEMISTRY question please help! Just need you to check my answer. THANKS?

[匿名]

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2017-10-25 10:12 am

How many moles of Sodium are there in 110 grams of NaHCO3?

[匿名]

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2017-10-25 8:47 am

Reaction between potassium iodide. and barium hydroxide?

[匿名]

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2017-10-24 5:26 pm

calculate the concentration of a OH- for an aqueous solution with a PH 9.60?

[匿名]

回覆: 2

2017-10-24 12:58 am

Chemistry question, please help?

[匿名]

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2017-10-23 2:30 pm

In what way will the calculated molar mass be affected if the precipitate is not heated to constant mass. **Please help 5 stars Chemistry***?

[匿名]

回覆: 2

2017-10-23 11:34 am

Organic chemistry question help?

[匿名]

回覆: 6

2017-10-22 9:11 pm

The point A(-6,1) is reflected over the point (-5, 3) and it's image is point B. What are the coordinates of point B?

[匿名]

回覆: 1

2017-10-22 5:41 pm

What is the bond order of CCl4?

[匿名]

回覆: 1

2017-10-20 11:50 pm

What is the empirical formula of the compound?

[匿名]

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2017-10-20 8:54 pm

Chemistry question?

[匿名]

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2017-10-20 10:36 am

How much sulfur dioxide would you need to completely react with 6.00 g O2 such that all reactants could be consumed?

[匿名]

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2017-10-19 12:12 am

Broasted-Lowry acid, help finding result?

[匿名]

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2017-10-18 1:15 pm

A piece of sodium metal undergoes complete reaction with water as follows: 2 Na(s) + 2 H2O(l) → 2 NaOH(aq) + H2(g)?

[匿名]

回覆: 1

2017-10-18 12:48 pm

0.5 mL of toluene react with 1.0 mL of 1 M solution of bromine in CH2Cl2. Calculate the number of mols of each reagent (bromine and toluene)?

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2017-10-18 11:22 am

Chemistry Question?

[匿名]

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2017-10-18 9:17 am

If 20.0 mL Ca(OH)2 with an unknown concentration is neutralized by 37.5 mL of 0.124 M HCl, what is the concentration of Ca(OH)2 solution?

[匿名]

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2017-10-17 10:38 pm

Which has the more exothermic electron affinity, the oxygen atom or O-? Explain why.?

[匿名]

回覆: 5

2017-10-17 5:48 pm

Making X the Subject question on photo.?

[匿名]

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2017-10-17 1:42 pm

Aln (x) +b ln (y) =......................?

[匿名]

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2017-10-16 7:59 pm

Write molecular, complete ionic, and net ionic equations for each of the following precipitation reactions.?

[匿名]

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2017-10-16 4:43 pm

When heated KlCO₃ decomposes into KCl and O₂. 2KClO₃-->2KCl+3O₂ If this reaction produced 81.5 grams of KCl, how much O₂ was produced?

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2017-10-13 1:20 pm

What is the oxidation number for S in Na2S4O6 ?

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2017-10-12 12:49 am

Draw the structure of the geometric isomer of 2-pentene that has the lower melting point. Thank you !?

[匿名]

回覆: 1

2017-10-11 3:46 pm

Help with Physics?