 Lv 2283 points

# Anonymous

• ### How fast is the top of the ladder sliding down the wall?

A 20ft ladder is leaning against a wall and begins to slide. How fast is the top of the ladder sliding down the wall as the instant of time when the bottom of the ladder is 12ft from the wall and is sliding away from the wall at a rate of 5ft/sec.

• ### At that moment, what is the rate of change of profit, dp/dt?

For Luce Landscaping, the total revenue and the total cost for yard maintenance of x homes are given by R(x)=1000x-x^2 and C(x)=3000+20x. Suppose that Luce is adding 10 homes per day at the moment when the 400th customer is signed. At that moment, what is the rate of change of profit, dp/dt?

• ### How do you get the integrated area of a GC peak? How is that then directly proportional to the relative molar amounts of the compounds?

I am also confused about the relative molar amounts. What is the units for that?

• ### Which statement is correct for this reaction?

CH3-(g) + NH3(g) ⇄ CH4(g) + NH2-(g)

NH3 acts as a base.

NH2- is the conjugate acid of NH3.

CH3- acts as a base.

CH3- is the conjugate acid of CH4.

All statements are false.

• ### How many grams of oxygen gas were collected?

A volume of 175 mL of oxygen gas is collected over water at 23.2°C. The atmospheric pressure for the day is 745 mm Hg. The vapor pressure of water at 23.2°C is 21.329 mm Hg.

• ### What is being oxidized? Reduced? What is the oxidizing agent? Reducing agent?

Determine the oxidation state of each element in the following reaction and then balance it in a base:

NO3-(aq) + Zn(s)  Zn(OH)42-(aq) + NH3(g)

• ### MnO4- + SO32- → MnO2 + SO42-?

Balance the following reaction in a base. What is being oxidized? Reduced? What is the oxidizing agent? Reducing agent?

• ### Which statement about a galvanic cell is true?

Oxidation occurs at the cathode .

Electrons flow from the anode to the cathode.

The cell reaction is nonspontaneous.

Electrons are transferred through the salt bridge.

The charge on the anode is positive.

• ### Which is an oxidation-reduction reaction?

Be2+ + 2e- à Be

Au3+ + 4 CN- à Au(CN)4-

N2 + 3 H2 à 2 NH3

Cu(NH)42+ + SO42- à [Cu(NH3)4]SO4

2 CrO42- + 2 H+ à Cr2O72- + H2O