Questions
Explain the differences between aragonite and conchiolin. How are these differences significant when it comes to...

  1. Explain the differences between aragonite and conchiolin. How are these differences significant when it comes to the creation of pearls?

In: Chemistry

A voltaic cell consists of a Pb/Pb2+ half cell and a Cu/Cu2+ half cell at 25C....

A voltaic cell consists of a Pb/Pb2+ half cell and a Cu/Cu2+ half cell at 25C. The initial concentrations of Pb2+ and Cu2+ are 0.0520 M and 0.150 M respectively.

Part A: What is the initial cell potential

*Write answer using two significant figures

Part B: What is the cell potential when the concentration of Cu2+ has fallen to 0.210 M

*Write answer using three significant figures

Part C: What is the concentration of Pb2+ when the cell potential falls to 0.350 V

*Write answer using three significant figures

Any help with this is greatly appreciated! Thank you in advance!

In: Chemistry

What is the change in enthalpy (∆H) when a 147g of ice at -23.7°C is heated...

What is the change in enthalpy (∆H) when a 147g of ice at -23.7°C is heated to a liquid at 66.5°C? The specific heats of ice, liquid water, and steam are 2.03, 4.18, and 1.84 J/g°C, respectively. For water, ∆Hvap = 40.67 kJ/mol and ∆Hfus = 6.01 kJ/mol.

In: Chemistry

Which of the following elements can be prepared by electrolysis of their aqueous salts: fluorine copper...

Which of the following elements can be prepared by electrolysis of their aqueous salts: fluorine copper nitrate calcium silver iodine potassium

Please explain as simply as possible as well

In: Chemistry

Calculate the Kf of Ag(NH3)2 + from Ag+(aq) + e- ⇋ Ag(s) E0= 0.81 V Ag(NH3)2+(aq)...

Calculate the Kf of Ag(NH3)2 + from

Ag+(aq) + e- ⇋ Ag(s) E0= 0.81 V

Ag(NH3)2+(aq) + e- ⇋ Ag(s) + 2NH3(aq) E0= 0.37 V

In: Chemistry

Natural gas (CH4) is burned to raise the temperature of 20 L of water in a...

Natural gas (CH4) is burned to raise the temperature of 20 L of water in a storage tank from 5.8 °C to 82.0 °C.

a) How much heat energy (in J) is absorbed by the water?

b) Assuming this was a closed system, how much heat energy (in J) was released by the burning natural gas?

c) What mass (in kg) of methane was burned?

d) If some heat released by the burning of natural gas was “lost” heating up the tank that holds the water, would this make the actual methane mass consumed higher or lower than what you just calculated? Why?

In: Chemistry

biochemistry : Explain with a drawing and 1-2 sentences the difference between “super secondray structure “...

biochemistry :

Explain with a drawing and 1-2 sentences the difference between “super secondray structure “ and “domain”

In: Chemistry

If a small amount of Ferrous Ammonium Sulfate is spilled when transferring it from the beaker...

If a small amount of Ferrous Ammonium Sulfate is spilled when transferring it from the beaker to the Erlenmeyer flask, how will this affect the calculated molarity of KMnO4?

In: Chemistry

Tetracaine Hydrochloride 0.5% (0.18 E Value) Sol. Epinephrine Bitartrate 1:1000 10 (0.18 E Value) Boric Acid...

Tetracaine Hydrochloride 0.5% (0.18 E Value)
Sol. Epinephrine Bitartrate 1:1000 10 (0.18 E Value)
Boric Acid q.s.
Purified Water ad 30.0
Make isoton. sol.
Sig. Eye drops.

The solution epinephrine bitartrate (1:1000) is already isotonic. How many grams of boric acid should be used in compounding the prescription?


Answer: 0.294g

In: Chemistry

14. a) What is the product when you react hydrochloric acid with metal? b) What is...

14. a) What is the product when you react hydrochloric acid with metal? b) What is the product when you react hydrochloric acid with carbonates? c) What is the product when you react hydrochloric acid with ammonia? d) What is the product when you react hydrochloric acid with hydroxide? e) Which of the reaction in a) through d) is most similar to the reaction which produces Benadryl? (look up an image of the ingredient label)

In: Chemistry

81Sr decays by positron emission with a half-life of 22.2 minutes. Starting with 885g of Sr-81,...

81Sr decays by positron emission with a half-life of 22.2 minutes. Starting with 885g of Sr-81, how much remains after 75.0 minutes?

In: Chemistry

Balance the following redox reaction, assume in basic conditions. SO 3 2- + CrO 4 2-...

Balance the following redox reaction, assume in basic conditions. SO 3 2- + CrO 4 2-  SO 4 2- + CrO 2 1-

In: Chemistry

For the following procedure: Nickel acetate added to a refluxing suspension of salen H2 in ethanol....

For the following procedure:

Nickel acetate added to a refluxing suspension of salen H2 in ethanol. Precipitated material collected via VACCUM FILTRATION (SUCTION). Product is N,N'-Bis(salicylaldehyde)ethylenediiminenickel(II), Ni(salen).

Question:
Why is the salenH2 filtered using vaccum filtration and not just gravity?

In: Chemistry

2. A mineral specimen is analyzed to determine the amount of cassiterite (SnO2) it contains. A...

2. A mineral specimen is analyzed to determine the amount of cassiterite (SnO2) it contains. A 0.5316 g sample of the mineral is prepared by dissolution of the solid into an acid solution. The Sn4+ cations in the solution are reduced to Sn2+. The solution is titrated with 0.01804 M K2Cr2O7 requiring 22.96 mL to reach the end point. The net ionic equation for the titration is given below.

3 Sn2+ (aq) + Cr2O72– (aq) + 14 H+ (aq) → 3 Sn4+ (aq) + 2 Cr3+ (aq) + 7 H2O (l)

a) Identify the oxidizing agent and the reducing agent in the titration reaction. (3 pts)

b) Determine the %SnO2 in the mineral sample. (3 pts)

In: Chemistry

The following cell reaction furnishes 0.62V. 2Fe3+(aq) + Sn2+(aq) ---> 2 Fe2+(aq) + Sn4+(aq) The maximum...

The following cell reaction furnishes 0.62V.

2Fe3+(aq) + Sn2+(aq) ---> 2 Fe2+(aq) + Sn4+(aq)

The maximum electrical energy per mole of Fe(III) ion is (1F = 9.65 x 104 C)

(A) 1.197 x 105 J/mole Fe(III) ion
(B) 2.394 x 105 J/mole Fe(III) ion
(C) 5.98 x 105 J/mole Fe(III) ion
(D) 5.98 x 104 J/mole Fe(III) ion

Correct answer is (C). Please explain why, thank you.

In: Chemistry