不用客氣

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回覆: 4

2016-11-26 7:12 am

What is the mass in the original mixture?

[匿名]

回覆: 1

2016-11-23 2:33 pm

why does fluothane,CF3CHBrCl, does not undergo elimination with hot ethanolic NaOH?

[匿名]

回覆: 1

2016-11-23 5:37 am

Chemistry Question?

[匿名]

回覆: 2

2016-11-21 4:14 pm

-32.0 °C, 4.96 L sample of mustard gas at 0.994 atm of pressure. What is the pressure, in atm, of that gas if compressed 1.92 L?

[匿名]

回覆: 1

2016-11-18 9:54 am

Titration?

[匿名]

回覆: 1

2016-11-16 6:01 am

How much heat would be released by the reaction of 0.95 g of Mg with excess HCl?

[匿名]

回覆: 1

2016-11-09 8:00 am

A 466g of water is heated from 8.50 degrees C to 74.60 C. Calculate the amount of heat absorbed (in kilojoules) by the water.?

[匿名]

回覆: 4

2016-11-08 3:24 pm

A mixture of oxygen,hydrogen, and nitrogen gases exerts a total pressure of 282 kPa. If the partial......?

[匿名]

回覆: 2

2016-11-04 5:12 am

Which neutral atom is isoelectronic with each of the following ions: F−, Ca2+, P3+, I−, Pb2+?

[匿名]

回覆: 1

2016-11-04 5:36 am

I need chemistry help!! A student fully combusts 697.10 grams of C12H22O11 in excess O2. How many grams of CO2 are produced?

[匿名]

回覆: 1

2016-11-04 12:56 am

Need help with Chem?

[匿名]

回覆: 2

2016-11-02 6:46 am

Aluminum, oxygen and carbon are each a(n)?

[匿名]

回覆: 2

2016-11-02 4:15 am

An empty beaker has a mass of 75.0 g. Salt is added to the beaker until it has a total mass of 108.06 g?

[匿名]

回覆: 1

2016-11-02 2:20 am

look up the density of ethylenediamine. calculate the number of grams and number of moles in 3.3 mL of ethylenediamine.?

[匿名]

回覆: 1

2016-10-26 5:17 pm

How do I calculate the concentration for Fe2+ in the solution??

[匿名]

回覆: 1

2016-10-26 7:48 am

925 ml of a 0.843M HNO3 solution is added to 1.5L of a 0.540M KOH solution. What is the pH of the mixture when the reaction is complete?

[匿名]

回覆: 1

2016-10-24 6:16 pm

The molar mass of washing soda, Na2CO3•10H2O(s), is Select one: a. 106.0 g/mol. b. 124.0 g/mol. c. 228.0 g/mol. d. 286.0 g/mol.?

[匿名]

回覆: 1

2016-10-24 4:44 pm

need major help with chemistry question?

[匿名]

回覆: 1

2016-10-24 7:14 am

What is the net ionic equation, including phases for the reaction AgNO3(aq) with K2SO4(aq)?

[匿名]

回覆: 1

2016-10-24 5:41 am

chemistry question about combustion?

[匿名]

回覆: 1

2016-10-24 4:17 am

When a 13.0 g sample of NaOH(s) dissolves in 400.0 mL of water to produce 413.0 g of solution in a constant pressure calorimeter,?

[匿名]

回覆: 1

2016-10-21 12:00 am

A sample of an ideal gas has a volume of 2.33 L at 285 K and 1.05 atm. Calculate the pressure when the volume is 1.13L and the temperature?

[匿名]

回覆: 2

2016-10-21 1:26 am

5.20 g He, 2.41 g F2, and 1.05 g Ar are placed in a 11.6-L container at 47.7 oC. What is the total pressure in the container?

[匿名]

回覆: 2

2016-10-21 1:13 pm

How many mmoles of HCl must be added to 130.0 mL of a 0.40 M solution of methylamine (pKb = 3.36) to give a buffer having a pH of 11.59?

[匿名]

回覆: 1

2016-10-21 5:01 am

Calculate ΔE, if q= 0.767 kJ and w= -850 J .?

[匿名]

回覆: 1

2016-10-19 4:53 pm

Given that the molar mass of H3PO4 is 97.994 grams, determine the number of grams of H3PO4 needed to prepare 1.50 L of 0.25 M H3PO4 solution?

[匿名]

回覆: 2

2016-10-19 2:59 pm

One mole of carbon dioxide at STP has a volume of?

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2016-10-19 7:13 am

If I increase the mass of magnesium powder added to a copper sulfate solution, will the temperature of the reaction rise? Why?

[匿名]

回覆: 1

2016-10-18 4:07 pm

How many grams is 6.511 mol tungsten (V) dichromate?

[匿名]

回覆: 1

2016-10-18 2:30 pm

how many terminal alkynes are there with the molecular formula C6H10?

[匿名]

回覆: 1

2016-10-18 10:06 am

Chemistry: Gas?

[匿名]

回覆: 1

2016-10-18 4:43 am

Strong-Acid, Strong Base Titration Questions?

[匿名]

回覆: 1

2016-10-18 6:56 am

which chemicals are undergoing an exothermic reaction when HCl is added to sodium benzoate and water?

[匿名]

回覆: 2

2016-10-18 1:34 am

Calculate the number of grams of oxygen required to convert 18.0 g of glucose to CO2 and H2O? Also compute the # of grams of CO2 produced?

[匿名]

回覆: 1

2016-10-16 5:51 pm

If you have 5.1g of N2 at a pressure of 100kPa and a temp of 25DegreesC, what is the volume in cm^3? Chem a level help - ideal gas equation?

[匿名]

回覆: 1

2016-10-16 5:49 am

Determining pH of a solution - addition of KOH to phosphoric acid. Did I solve this problem correctly?

[匿名]

回覆: 1

2016-10-16 8:07 am

1.34g of magnesium are added to 120cm^3 of 0.200mol/dm^3 solution of silver nitrate..what mass of silver will be formed?

[匿名]

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2016-10-14 4:41 pm

what metal element loses two electrons when it reacts to gain a 2+ charge the element has two shelld?

[匿名]

回覆: 1

2016-10-14 9:37 am

At 25 degree celsius, the equilibrium constants K1and K2 in the reactions 2NH3<---> N2+3H2=K1 And 1/2N2+3/2H2--->NH3 =K2 Are related as?

[匿名]

回覆: 1

2016-10-14 3:59 am

What is the volume of 6.0M sulfuric acid needed to neutralize the excess hydroxide?

[匿名]

回覆: 2

2016-10-11 6:13 pm

I need to make 10 ml of a 10 mM NaOH solution. I have a 1 M stock. How many ul of the stock do I need to use?

[匿名]

回覆: 2

2016-10-06 10:48 am

Atomic size of S is bigger than O Explain...?

[匿名]

回覆: 2

2016-10-05 6:11 pm

Before the first endpoint only K3PO4 is reacting. PO4^3– (aq) + H3O+ (aq) ---> HPO4^2– (aq) + H2O (l)?

[匿名]

回覆: 10

2016-10-05 7:23 am

y=12x−1 in standard form?

[匿名]

回覆: 1

2016-10-04 9:03 am

What makes pk2 of fumaric acid smaller than of maleic acid?

[匿名]

回覆: 1

2016-10-04 4:40 am

Final temperature?

[匿名]

回覆: 1

2016-10-03 5:40 am

A 57.17-g sample of Ba(OH)2 is dissolved in enough water to make 1.800 liters of solution.?

[匿名]

回覆: 4

2016-10-02 6:58 pm

to a solution you have added hydrogen ions to reduce the pH by 1. By how much has the concentration of hydrogen ions been changed?

[匿名]

回覆: 1

2016-10-02 4:51 am

Maximum wavelength Please help?

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回覆: 1

2016-09-30 9:45 am

The percentage of sulfur in coal be determined by burning a sample of the solid and passing the resulting sulfur dioxide gas into a solutio?