BERIT Q2: Variations in average atomic mass may be observed for elements obtained from different sources. Consider two sources of lithium: a mineral that is 7.50% Li and 92.50% Li, which have masses of 6.01512 amu and 7.01600 amu, respectively, and a recycled military source, that is only 3.75% Li (and the rest is "Li). Calculate the average atomic mass values for each of these two sources. Given: Two minerals w/ masses

H. H. Three moles of the compound in the figure above would weigh how many grams? (The atomic masses, in daltons, are approximately 12 for carbon, 1 for hydrogen). O=U エーO CH

A compound has carbon, hydrogen and oxygen.  Use the following data to calculate its empirical formula.  In a 100 g sample of the compound the following amounts of each element are present: carbon: 63.15 g hydrogen: 5.30 g oxygen: 31.55 g Show all of the steps of your calculations.

The chemical Oswegium pantherides formula is Os3Pa2. Oswegium’s (Symbol Os) atomic mass is 10 grams and pantheride ‘s (Symbol Pa) atomic mass is 5 grams. Calculate the percent composition of Oswegium in Oswegium pantheride ( Os3Pa2).

When a chemical reaction occurs, atoms rearrange to form now compounds, but no new atoms are created nor are any destroyed This concept is called conservation of mass. Mass conservation can be seen in a balanced chemical equation where the numbers of each kind of atom are the same on both sides of the reaction arrow. The figure (Figure 1) shows the reaction of element A (lavender spheres) with element B (tan spheres). Write the balanced chemical equation for this reaction in terms of A and B. Express your answer as a chemical equation. When balancing chemical equations with polyatomic ions, it may help to balance the ion as a whole. For example, the ion PO_4^3 can be treated as a unit and balanced in both the reactants and the product, or you can break it down and balance each atom separately. Phosphoric acid reacts with magnesium hydroxide to produce magnesium phosphate and water via the following reaction: Balance the equation, then enter the coefficients, in order, in the answer…

9. How many hydrogen atoms are there in 500.0 L of water? (dH₂O = 1.00 g mL¯¹) A: 3.34 x 1028

Determine the number of atoms in 53.0 grams of bromine, Br. (The mass of one mole of bromine is 79.90 g.) atoms 1 3 6. C 7 8. 9. +/- х 100

Is this correct answer?

Performing the same experiment described on your lab manual, a student used a 0.400 g sample of Alka-Seltzer and the mass of CO2 was found to be 0.114 g. Based on this result, answer the following questions: Determine the % mass of NaHCO3 in the sample. (enter your answer to 3 significant digits) Determine the mass of NaHCO3 in the tablet assuming the mass of the tablet is 3.50 g. (enter your answer to 3 significant digits)