True or false, The atomic number of an element is a whole number that decreases as you read across each row of the periodic table from left to right.

This graph gives information on changes in sea ice extent in the arctic ocean over a 30-year span. the overall trend shows in the ice extent. to address the trend, scientists need to ask themselves, one direct consequence of the trend is that

An aqueous solution of potassium hydroxide is standardized by titration with a 0.194 m solution of hydrobromic acid. if 25.2 ml of base are required to neutralize 24.2 ml of the acid, what is the molarity of the potassium hydroxide solution? m potassium hydroxide

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)