What is the first f element in the 6^th period to which Hund's rule must be applied when writing the orbital diagram?

Can someone please give me the chemical equation and directions on how to test for each individual solution below and how to tell if my solution has one of each category? So a test for HCl and HNO3 excetera.?

Acid-HCl,HNO3,H2SO4

Base-NaOH, NH3, Na2S

Chloride Salt-NaCl,BaCl2,CuCl2

Nitrate salt-AgNO3,Cu(NO3)2, Fe(NO3)3

Sodium Salt-NaI,Na2SO4,Na2CO3

Cu(II) sulfate exists as a hydrate. It has many practical uses including use as a fungicide and pesticide. When mixed with chromium and arsenic it forms the wood preservative called CCA. CCA was used in pressure treated wood to protect wood from rotting due to insects and microbial agents. Because CCA-treated wood contains toxic heavy metals, its use has been discontinued for home use and children’s play sets.

A chemist is given a sample of the CuSO₄ hydrate and asked to determine the empirical formula of it. The original sample weighed 42.75 g. After heating to remove the waters of hydration, the sample weighed 27.38 g. Determine the formula for this hydrate.

Please show all work!

Q1)A compound of molar mass 213 contains only carbon, hydrogen, iodine, and oxygen. Analysis shows that a sample of the compound contains 6 times as much carbon as hydrogen, by mass.

Part A

Calculate the molecular formula of the compound.

Express your answer as a chemical formula. Enter the elements in the order: C, H, O, I.

Q2) A particular brand of beef jerky contains 6.01×10⁻²% sodium nitrite by mass and is sold in an 8.00-oz bag.

What mass of sodium does the sodium nitrite contribute to sodium content of the bag of beef jerky?

Express your answer to three significant figures and include the appropriate units.

calculate the partial pressure of CO2 over calcium carbonate at 1000K

Derive planar density expressions for BCC (110) planes in terms of the atomic radius R.

2. Which gas has the lowest density at 25 °C and 1 atm?

Select one:

a. O₂

b. Ar

c. N₂

d. F₂

e. C₃H₈

4. If the volume of a confined gas is expanded to four times the original volume while its temperature remains constant, what change will be observed?

Select one:

a. The pressure of the gas will decrease to 1/4 its original value.

b. The pressure of the gas will decrease to 1/2 its original value.

c. The pressure of the gas will remain unchanged.

d. The pressure of the gas will increase to twice its original value.

e. The pressure of the gas will increase to four times its original value.

5. 36.6 L of He gas at STP is pumped into a 10.0-L tank containing 1.0 atm of O₂ at 25 °C. What is the total pressure in a tank at 25 °C?

Select one:

a. 2.0 atm

b. 5.0 atm

c. 5.4 atm

d. 8.0 atm

e. 8.8 atm

Write the balanced complete ionic equations and net ionic equations for the reactions that occur when each of the following solutions are mixed. (Type your answers using the format [NH4]+ for NH4+ or Ca3(PO4)2 for Ca3(PO4)2. Use the lowest possible coefficients.)

(a) Cr2(SO4)3(aq) and (NH4)2CO3(aq)

complete ionic equation:
  (aq) +  CO32-(aq) +  Cr3+(aq) +  SO42-(aq)    (s) +  NH4+(aq) +   (aq)

net ionic equation:
Cr3+(aq) +   (aq)    (s)




(b) FeCl3(aq) and Ag2SO4(aq)

complete ionic equation:
  (aq) +  Cl-(aq) +  Ag+(aq) +  SO42-(aq)    (s) +  Fe3+(aq) +   (aq)

net ionic equation:
Ag+(aq) +   (aq)    (s)




(c) Al2(SO4)3(aq) and K3PO4(aq)

complete ionic equation:
  (aq) +  PO43-(aq) +  Al3+(aq) +  SO42-(aq)    (s) +  K+(aq) +   (aq)

net ionic equation:
Al3+(aq) +   (aq)    (s)

FAST ANSWER PLEASE FOR BUFFER SOLUTION QUESTION. Would appreciate full working out thanks.

Solution C is made by mixing 55.6 mL of 0.16 M ammonium chloride (NH₄Cl) with 60.3 mL of 0.26 M ammonia solution.

pKa(NH4+) = 9.24

a) Calculate the pH of Solution C.

b) Calculate the pH of the buffer Solution C if 0.14 g of NaOH (molar mass = 40.0 g/mol) is added (assuming no change in volume).

Which reactant, and how much of it, remains after the reaction of 40.0g of V₂O₅ (FW=181.9g/mol) with 40.0g of calicuim based on the following chemical equation?

V₂O₅ + 5Ca----> 2V+5CaO

Possible Answers

0.810g Ca

3.6g Ca

.801g V₂O₅

3.6g V₂O₅

4.52g V₂O₅

1. The following question deals with nickel(II) nitrate hexahydrate.

   1. a) What is the molecular formula for nickel(II) nitrate hexahydrate?

   2. b) What is the molar mass of nickel(II) nitrate hexahydrate?

   3. c) What is the concentration of a nickel(II) nitrate stock solution when 114.2 g of nickel(II) nitrate hexahydrate is dissolved to a final volume of 250.0 mL?

   4. d) What is the concentration of a dilute nickel(II) nitrate solution after 1.55 mL of the above stock solution is diluted to a final volume of 25.0 mL?

A student dissolved 5.05 g of KNO3 in 100.302 g of water. The temperature changed from 25 to 21.7°C. Calculate the enthalpy of solution the student experimentally found in kJ/mole of KNO3. Is this an endothermic or an exothermic
reaction?

Calculate the equilibrium concentration of [FeSCN2+] in Part A if 10.0mL of 2.0x10-3M KSCN and 25.00mL of 0.0020M Fe(NO3)3 are diluted to 100.0mL.

Hint: Answer includes 2 significant figures.

Hint: See "PREPARATION OF STANDARD SOLUTIONS" on page 3-2.

Hint:

PREPARATION OF STANDARD SOLUTIONS

To get solutions with known [FeSCN²⁺], the following process will be used. You will prepare standard solutions by mixing carefully measured volumes of solutions of Fe³⁺ (using Fe(NO₃)₃ stock solution) and SCN^– (using KSCN stock solution) of known concentrations. These volumes for standard solutions A–F are listed in the Standard Solutions Table (Table 3-1) in Part A, step 6. The key to getting a known concentration of FeSCN²⁺ in each of these solutions is that the initial concentration of Fe³⁺ is much greater than the initial concentration of SCN^– ion. When the Fe³⁺ concentration is in large excess, the equilibrium will shift (according to Le Châtelier’s Principle) to the product side until virtually all the SCN^– is converted to FeSCN²⁺. Thus the equilibrium concentration of FeSCN²⁺ in a standard solution will be virtually the same as the initial concentration of SCN^– in the solution. This initial value, [SCN^–]_initial, which equals [FeSCN²⁺] in the mixed standard solution, can be calculated from the volume and molarity of the SCN^– stock solution (mol SCN^– = M × V) and the final total volume (in L) of the mixed standard solution. With these calculated values for [FeSCN²⁺] and the measured absorbances of these standard solutions, a Beer’s law plot can be obtained.

Write the balanced equation for the reaction of aqueous Pb (ClO3)2 with aqueous Nal. Include phases

What mass of precipate will form if 1.50L of highly concentrated Pb(ClO3)2 is mixed with 0.400L of 0.110 M Nal?