Today in grassfield chemistry class we are testing how far we can launch pumpkin seeds with chemical reactions. Based on calculations the true value should be 13.4 cm. Group 1 Group 2 Group 3 Trial 1 13.9 cm 13.5 cm 13.0cm Trial 2 13.0 cm 13.1cm 12.9cm Trial 3 17.0 cm 13.7cm 13.0 cm Which is the group with the most precise data? Which is the group with the most accurate data?

How can we find the atomic mass of the planet? What are the steps?

Five calcite, CaCO3CaCO3 (MM 100.085 g/mol), samples of equal mass have a total mass of 12.1±0.1 g12.1±0.1 g. What is the average mass and absolute uncertainty of calcium in each sample? Assume that the relative uncertainties in atomic mass are small compared the uncertainty of the total mass.

- 23 An oxygen atom has a mass of 2.66 × 10 g and a glass of water has a mass of 0.050 kg. Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of oxygen atoms? Round your answer to 3 significant digits. How many moles of oxygen atoms have a mass equal to the mass of a glass of water? Round your answer to 2 significant digits. 0 g x10 X

Why must atomic masses be weighted averages rather than conventional average values?

Students conducted an experiment to observe the properties of four elements. The results of their observations are in the table below.   Based on the information in the table, Sample 3 would likely be classified as a(n) —    alkali metal halogen noble gas transition metal

Write a balanced equation for the following by inserting the correct coefficients (if a coefficient = = 1, enter "1" in the provided box). Ca3(PO4)2(s) + C(s) + SiO₂ (s)→ CaSiO3(1) + -P4(g) CO(g) +

In this station, you will find an empty box that contains air. The density of air is 1.19 g/L. It is 78.0% nitrogen. How many nitrogen (N2) molecules are in this box? (Remember: 1 cm3 = 1 mL.) dimensions measured: 21 cm x 14.5 cm x 9.00 cm (cm3)

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2.) Suppose you're attempting to measure the density of a liquid that is highly volatile (it evaporates quickly). If you first measure the volume and then several minutes later you measure the mass of the liquid will the measured density be higher than the true value, lower than the true value, or the true density of the liquid. [It helps to understand this problem with the density equation.]