What happened when hydrogen passes over the heated lead oxide

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

If 3.00 g of titanium metal is reacted with 6.00 g of chlorine gas, cl2, to form 7.7 g of titanium (iv) chloride in a combination reaction, what is the percent yield of the product?

6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.