Chemistry Forum

Calculate the mass of CaF2 produced when 5g of Ca(NO3)2 is mixed with 3g of NaF in water, with a final volume of 500 mL. Ksp is 3.5E-11 for the system. My attempt to answer: Reaction equation is Ca(NO3)2 + 2NaF → CaF2 + 2NaNO3, we have 3.047e-2 moles of Calcium Nitrate and 7.145e-2 moles of Sodium F...

For readers and viewers , detailed answer to this question is not transferrable

How much heat is produced when 100 mL of 0.250 M HCl (density, 1.00 g/mL) and 200 mL of 0.150 M NaOH (density, 1.00 g/mL) are mixed? HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l) ∆H°₂₅°c = −58 kJ If both solutions are at the same temperature and the heat capacity of the products is 4.19 J/g℃, how much will...

Initial temperature of iron was 100.0℃ and its final temperature is equal to final temperature of the system which is 23.59℃. So ∆T for 48.59 g sample of iron is 100.0℃- 23.59℃= 76.41℃. If you read carefully, you will notice that the questioner asked how much heat absorbed by coffee cup calorimeter,...

This reaction released 1670.743 J of heat out of which 847.04 Jwas absorbed by coffee-cup calorimeter and 823.70 J was absorbed by water.

Both the reactions are endothermic , but your negative signs implies both reactions are exothermic. How is that?

Given the following: Fe + CO2 → Fe2O3 + CO △ H°= + 25.0 kj

a) Give the balanced thermochemical equation.
My answer:
2Fe(III)(s) + 3CO2 (g) → Fe2O3 (s) + 3CO (g)

b) Is this reaction exothermic or endothermic?
My answer: This reaction is endothermic.

1]Consider the following balanced reaction: 2A_2 + 3B \rightarrow C_2 + 2D What is the enthalpy of reaction if the enthalpy of formation of the compounds is given as A_2 = 7.78 kJ/mol; B = -18.43 kJ/mol; C_2 = 0 kJ/mol; D = 9.96 kJ/mol. Record your answer in scientific notation using 3 significant f...

A 48.59 gram sample of iron (with a heat capacity of 0.450 J/g ºC) is heated to 100.0 ºC. It is then transferred to a coffee cup calorimeter containing 66.51 g of water (specific heat of 4.184 J/ g ºC) initially at 20.63 ºC. If the final temperature of the system is 23.59 ºC, how much heat was absor...

Correct answer provided is Heat capacity is Extensive property. But you said both a) and b) are correct. How is that?

1)A gold block has a mass of 0.630 kg and is initially at a temperature of 15.4℃. How much energy must be transferred to the block as heat for it to reach a final temperature of 49.3℃? Use c_{gold }=452 J/kg•K for the specific heat value of gold. a) 4,390 J b) 14,000 J c)-14,000 J d)-9,650 J e) 9,65...

Thanks for your correct answer for derivation of unit.

Potential energy formula is \(PE=\frac{kq1q2}{r}\)where \(k=\frac{8.99e9J*m}{C^2}\) How is this k value derived? What is \(\frac{J*m}{C^2}?\)

The salt MX2 has a K_{sp} of 4.64e-9. If equal volumes of 0.00061 M M(NO3)2 and 0.001 M NaX are mixed, will solid form? M represents metal and X represents anion. What is your answer? Yes or No? My answer is No. I computed the answer as follows: Firstly, we have to determine the concentration of M a...

This question presents analytical data from which you are required to determine mass % composition for a compound of up to four elements. A sample of a compound containing C,H,S and Cl is subjected to combustion analysis to determine the quantities of C and H present. Using a second sample, the S is...