What’s the name of equipment shown below?  

In an experiment, a student placed a beaker on a balance and the mass of the beaker was 132.5 grams.  The student then added some iron to the beaker, the mass increased to 147.3 grams.  How many moles of iron did the student have? (enter your answer with 3 decimal places and no units, the understood unit is mole)

45.0 mL of 6.0M HCl (aq) was placed placed into an empty flask which has the mass of 50.000 grams.  Total mass became 95.020 grams.  After adding 2.000 gram of CaCO3 to the open flask containing HCl (aq), a reaction was observed with gas bubbles.  After the reaction comes to completion, the total mass of the flask and products became 96.148 grams.  What’s the mass of the gas produced by this reaction? Mark your answer next to words “Final answer is”.  You must follow significant figure rules.  Show your work here to receive any partial credit. 

Provide the probability in terms of a decimal or percent. 1) Assume that blood pressure readings are normally distributed with a mean of 120 and a standard deviation of 8. If 100 people are randomly selected, find the probability that their mean blood pressure will be greater than 122.   2) Assume that the salaries of elementary school teachers in the United States are normally distributed with a mean of $32,000 and a standard deviation of $3000. If 100 teachers are randomly selected, find the probability that their mean salary is less than $32,500.

Match each of the following compounds (note all the number in the formula are subscripts) to their molecular shape name. (hint: draw the Lewis dot structure for each)

Determine the formula mass for Copper (VI) sulfide an imaginary compound. (Enter your answer with 4  sig figs and no units).  

Construct the appropriate confidence interval. 14) Construct the indicated confidence interval for the population mean

Explain. 8) Given the same sample statistics, which level of confidence will produce the narrowest confidence interval: 75%, 85%, 90%, or 95%? Explain your reasoning.

Find the minimum sample size. 18) A researcher wishes to estimate the number of households with two cars. How large a sample is needed in order to be 95 % confident that the sample proportion will not differ from the true proportion by more than 5 %? A previous study indicates that the proportion of households with two cars is 22%.

Use the Central Limit Theorem to find the mean and standard error of the mean of the indicated sampling distribution. 3) The amounts of time employees of a telecommunications company have worked for the company are normally distributed with a mean of 5.4 years and a standard deviation of 2.1 years. Random samples of size 12 are drawn from the population and the mean of each sample is determined.