不用客氣

[匿名]

回覆: 1

2017-10-20 8:50 pm

enthalpy change for the first reaction? P4 + 6Cl2 → 4PCl3 ΔH = P4 + 10Cl2(g) → 4PCl5(s) ΔH = -1,777.5 PCl3(l) + Cl2 → PCl5(s) ΔH = -127.2?

[匿名]

回覆: 2

2017-10-20 11:29 am

Chemistry, please help! I keep getting the wrong answer! Due at midnight?

[匿名]

回覆: 1

2017-10-20 8:29 am

Chemistry help please! thank you :)?

[匿名]

回覆: 1

2017-10-18 1:10 pm

Aluminum will react with bromine to form aluminum bromide (Al2Br6). What mass of bromine (g) is needed to form 1.1 mol of Al2Br6? Plz help!?

[匿名]

回覆: 3

2017-10-18 1:50 pm

The forces that hold atoms or ions together are?

[匿名]

回覆: 2

2017-10-18 11:32 am

In the Lewis structure of SOF2, the total number of electron lone pairs is?

[匿名]

回覆: 1

2017-10-18 9:40 am

What is the empirical formula of a compound with 5.02g of C, .42g of H, and 1.33g of O?

[匿名]

回覆: 1

2017-10-17 6:51 pm

Aspirin (C9H8O4) is produced by the reaction of salicylic acid (M = 138.1 g/mol) and acetic anhydride (M = 102.1 g/mol).?

[匿名]

回覆: 5

2017-10-17 7:22 pm

I do not know how to solve this. (Binomial Theorem) UPDATED?

[匿名]

回覆: 3

2017-10-17 2:16 pm

Trig Use the given information about θ to find the exact values of the following?

[匿名]

回覆: 1

2017-10-16 10:40 pm

How much zinc in grams would be needed to produce 300 grams of copper metal from any soluble copper II salt? (atomic weight of zinc=65.41?

[匿名]

回覆: 1

2017-10-16 6:29 pm

what is the enthalpy per mole of aluminum oxide if the reaction of 5.32g of aluminum oxide release 38.93 KJ of heat?

[匿名]

回覆: 3

2017-10-13 11:58 pm

A sample of 5.50 g of Mg(OH)2 is added to 25.4 mL of 0.150 M HNO3. 1)Write the chemical equation for the reaction that occurs.?

[匿名]

回覆: 1

2017-10-13 4:24 pm

State the formula of the conjugate base of: H3O + and H2PO- 4?

[匿名]

回覆: 1

2017-10-11 4:10 pm

Probability help?

[匿名]

回覆: 2

2017-10-11 11:57 am

What is the name of the compound RbH2?

[匿名]

回覆: 2

2017-10-09 3:29 pm

What are the products of chromium 6 and ferrous sulfate (FeSO4)?

[匿名]

回覆: 4

2017-10-09 12:01 am

What color is typically associated with 600 nm? What is its frequency and period?

[匿名]

回覆: 1

2017-10-08 8:25 pm

Chemistry Sodium chloride is a ionic compound it has a high melting point. It will not conduct electricity when solid but will when melted.?

[匿名]

回覆: 1

2017-10-06 8:43 pm

Are both methanol and aq. Methanol protic solvents and If aq.methanol is protic the why cuz it breaks as CH3+ and OH-?

[匿名]

回覆: 1

2017-10-04 11:58 pm

If a 0.64 mole of B is reacted with excess A according to the following reaction: 2A+7B -> 4Q+5R?

[匿名]

回覆: 2

2017-10-03 7:40 am

How do you name this alkene?

[匿名]

回覆: 1

2017-10-03 2:52 pm

You have 2 stock solutions with the following concentrations. Glucose: 1.9 g/L. NaCl: 698 mg/L.?

[匿名]

回覆: 2

2017-10-03 12:05 am

Help please, tan Θ=15/8 with Θ in quadrant 1 find cos 2 Θ? what topic is this and how do I solve it? please?

[匿名]

回覆: 1

2017-10-02 11:19 am

please help with chemistry problem?

[匿名]

回覆: 3

2017-10-01 5:15 pm

What is the slope m of a line that is perpendicular to the line represented by x = 9? (If an answer is undefined, enter UNDEFINED.) M=?

[匿名]

回覆: 1

2017-09-30 12:30 pm

I have revision questions that i have not completed in 7+ years. Needing some help prior to my exam. How would you answer this question?

[匿名]

回覆: 11

2017-09-27 11:11 pm

Write the ratio: 2 4/5 to 4 3/5 as a fraction in lowest terms.?

[匿名]

回覆: 2

2017-09-27 4:48 pm

A stone is thrown vertically upward with a speed of 22.0 m/s?

[匿名]

回覆: 2

2017-09-27 2:09 pm

A 300 kg weather rocket is loaded with 100 kg of fuel and fired straight up. It accelerates upward at 26 m/s2 for 36 s, then runs out of...?

[匿名]

回覆: 3

2017-09-27 3:38 am

Chemistry Calorimetry problem below please explain. The steps you take to get the answer. I will AWARD BEST ANSWER?

[匿名]

回覆: 2

2017-09-27 12:20 am

What are the name of the compounds in order? From top to bottom.?

[匿名]

回覆: 6

2017-09-26 5:15 pm

If X - 42 = 0 then X = ?

[匿名]

回覆: 10

2017-09-26 5:15 pm

If X - 42 = 0 then X = ?

[匿名]

回覆: 1

2017-09-26 2:44 pm

Solve 2cos2x =sins-1?

[匿名]

回覆: 1

2017-09-25 9:39 pm

CHEM HELP SOS?

[匿名]

回覆: 2

2017-09-25 8:15 pm

Energetics Question (Chemistry)?

[匿名]

回覆: 3

2017-09-25 1:26 am

How many grams or moles of pure HCl are needed to completely react with 0.581 grams of Na2CO3?

[匿名]

回覆: 2

2017-09-24 10:51 pm

Which mass measurement contains a total of three significant figures? A)22.0 g B) 22.00 g C) 220 g D) 2200 g?

[匿名]

回覆: 1

2017-09-24 7:57 pm

Isooctane (2,2,4-trimethylpentane), one of the many hydrocarbons that make up gasoline, burns in air to give water and carbon dioxide. What?

[匿名]

回覆: 5

2017-09-21 12:50 am

What is 13x-2x^2=15?

[匿名]

回覆: 3

2017-09-19 6:13 pm

a 0.5kg ball is dropped from a height of 3 metres. what is its gravitational potentiial energy when it is released?

[匿名]

回覆: 2

2017-09-15 11:25 pm

How many moles of KF can be produced when 2.67 mol K reacts with 9.01 mol F2?

[匿名]

回覆: 1

2017-09-13 12:57 pm

Help with Chemistry problems.?

[匿名]

回覆: 2

2017-09-13 12:22 am

The pH of a solution is 6.72 ± 0.03. What is the concentration of H in the solution and its absolute error? [H+]= __M ± ___M?

[匿名]

回覆: 3

2017-09-12 7:03 pm

4^x-(2*25^x)-10^x <0 solve the inequality?

用戶110527

回覆: 2

2017-09-12 2:56 pm

Need a help in • Geometry •......?

[匿名]

回覆: 2

2017-09-11 12:06 pm

Organic Chem question!? HARD?

[匿名]

回覆: 3

2017-09-05 12:25 am

If the Ksp value of MX,M2X and MX3 are same then find out the solubility order.?

[匿名]

回覆: 2

2017-09-04 1:52 pm

If a,b,c are real numbers and a not equal to b then prove that (a-b)x²-5(a+b)k-2(a-b)=0 has two distinct real roots?