Calculate the number of moles of Cl2 molecules in a sample that contains 7.102 × 1025 molecules of Cl2.

A hydrocarbon has the formula C3H4. What is the percent by mass of carbon in the compound?  Show all work STATE JUST YOUR ANSWER INCLUDING UNITS IN THE TEXT BOX BELOW. Do not show work in the text box.  # your question on scratch paper and label answer,  Include units   If your number is in scientific notation use the superscript or subscript buttons in the task button up in the task bar above. Show all work or receive no credit Show work to webcam upon completion of this problem.  Show units and chemical name or formulas if applicable.   Spelling counts.  Sig Figs will not count unless otherwise stated.  You will be asked to scan all your work at the end of the exam.   Show your final answer in the text box

How many grams of F2 are there in 1.84 mol F2?

If a sample of blood was found to have a density of 1.05 g/mL.  What is the mass (ng) of 66 mL of this material?  Express your answer in significant figures.   STATE JUST YOUR ANSWER INCLUDING UNITS IN THE TEXT BOX BELOW. Do not show work in the text box.  # your question on scratch paper and label answer,  Include units   If your number is in scientific notation use the superscript or subscript buttons in the task button up in the task bar above. Show all work or receive no credit Show work to webcam upon completion of this problem.  Show units and chemical name or formulas if applicable.   Spelling counts.  Sig Figs will not count unless otherwise stated.  You will be asked to scan all your work at the end of the exam.   Write your final answer in text box.

Complete the following operation and express your answer to the correct number of significant figures and units: 9.370 x 10-5 cm-2.25 x 10-6 cm = _____________________.    You do not need to show work for this problem.   Write your final answer in text box.

The name for the compound Sn(CH3COO)2 is ______________  .____________________________________ no work needed to be shown Write your final answer in text box.

Write the correct formula for mercury(II) cyanide.____________________________________ no work needed to be shown Write your final answer in text box.

The name for MnO2 is ____________________________________ no work needed to be shown Write your final answer in text box.

Determine the number of protons and the number of neutrons in an atom of I-127.

A researcher claims that the average number of credit cards an adult U.S. person is 2. 1. Which of the following choices expresses the claim symbolically.  [1] Choice A: