2H2+O2→2H2O There are four atoms of hydrogen (H) before the reaction. How many atoms of hydrogen are present after the reaction?

4

8

5

2

The alkali metals (group 1) consist of lithium (3), sodium (11), potassium (19), rubidium (37), cesium (55), and francium (87). they are soft, metallic solids with low densities and low melting points. based on the data shown in figure 1, how many valence electrons do alkali metals share?

Calculate: select the worksheet tab. this tab you calculate the analyte concentration.  fill in the first set of boxes ("moles h2so4" and "moles naoh") based on the coefficients in the balanced equation. (if there is no coefficient, the value is 1.)  record the appropriate volumes in the "ml naoh" and "ml h2so4" boxes.  record the concentration of the titrant in the m naoh box. click calculate. what is the concentration listed

Light waves travel than sound waves.