Nicole

https://www.youtube.com/watch?v=nQvo-ljQHnc

A sinusoid has a maximum value of 6 and a minimum value of -4. What is the amplitude?  

If a 10 percent increase in the price of good X results in a 20 percent increase in the quantity of good Y demanded, which of the following is true?

Good X and good Y are complementary goods, and the cross-price elasticity is −0.5. bGood X and good Y are normal goods, and the income elasticity is +2. cGood X and good Y are substitute goods, and the income elasticity is +2. dGood X and good Y are complementary goods, and the cross-price elasticity is −2. eGood X and good Y are substitute goods, and the cross-price elasticity is −2.

How do I find absorbance? I have this data

3mL stock 7mL water .350Molarity

The original stock was .500Molarity and 10mL, the 3 and 7 are from a new concentration which is what I have to find the absorbance for

A 0.255g sample of organic alcohol (containing CHO) is burned, producing 0.561g of CO2 and 0.306g H2O. What is the empirical formula of the alcohol?

1. Mass of empty container 22.47

    Initial mass of sample and container 25.29

    Mass of sample and container after heating 24.43g

Student 1 is assigned the task of determining the number of moles of water in one mole of CuSO4 x nH2O

a) determine grams of anhydrous product

b) calculate total number of moles of water lost when the sample was heated

c) determine the formula of the hydrated compound

Student 2 does the lab as well. His data yields a different result. After doing his calculations, he determines that the formula of the hydrate is CuSO4 x 8H2O. The actual formula is CuSO4 x 5H2O. 

The students were then asked to analyze their lab for error. One student said that as the copper sulfate hydrate was heating, small pieces of it popped out of the crucible and at the end of the lab, he noticed that there were several blue crystals on the table around the Bunsen burner. The other student thought that he didn’t hear the hydrate long enough. 

B) identify the student (1 or 2) who did not beat the hydrate long enough. Explain how that error affected his calculations and final formula.

How do you find dry mass? We are doing a lab of “gravimetric analysis of a metal carbonate” and one of the pre lab questions is to find the dry mass. The M stands for the mystery element we need to find.

The reaction is CaCl2(aq) + M2CO3(aq) —> CaCO3(s) + 2MCl(aq)My friend and I found that the mass of M2CO3 is 2.13g in this experiment, and the mass of CaCO3 is 1.838g. The question being asked is “calculate the dry mass of M2CO3 used”

How do you find dry mass? We also have other measurements I didn’t list here... if those are needed please tell me

My chemistry teacher was not good during distance learning at the end of last year so I have no idea what to do for these problems in my AP chem summer work. 

1. A 15.3g piece of metal with an initial temp of 100.9°C is added to 90.3g of water with an initial temp of 20.9°C. The final temp is 27.0°C. Calculate the specific heat of the metal.

2. A 10.4g piece of metal with an initial temperature of 100°C is added to 33.3g of water with an initial temp of 22.0°C. The specific heat of the metal is 0.593J/g°C. Calculate the final temp. (Cp for water is 4.18 J/g°C)

3. What is the enthalpy of solution in kJ/mole if 5.05g of NaOH is dissolved into 124g of water? The temp of the water changes from 23.1°C to 26.4°C. Is this exothermic or endothermic? Explain.

4. When ice at 0°C melts to liquid at 0°C, it absorbs 0.334 kJ of heat per gram. Suppose the heat needed to melt 38.0 g of ice is absorbed from the water contained in a glass. If this water has a mass of 0.210kg and a temperature of 21.0°C, what is the final temp of the water? (Note that you will also have 38.0g of water at 0°C from the ice.)