Which elements did the Curies discover?

thorium and polonium

radium and uranium

radium and polonium

uranium and curium

Which is a balanced chemical equation? a) C7H16 + 5O2 6CO2 + 4H2O b) C7H16 + 11O2 7CO2 + 8H2O c) C7H16 + 14O2 7CO2 + 5H2O d) C7H16 + 22O2 14CO2 + 16H2O

Suppose that in the synthesis of benzoic acid, a student uses 1.333 grams of magnesium, 7.122 grams of bromobenzene, and 15.933 grams of dry ice. if the mass of benzoic acid obtained were 4.66, what was the percent yield?'

How many hydrogen atoms are missing in ethane compared to ethane

A physician has ordered 0.50 mg of atropine, intramuscularly. If atropine were available as 0.25 mg/mL of solution, how many milliliters would you need to give?

There are 18 periods in the periodic table. Which answer choice rewords the false statement so it is true?

A flask contains 4.4g of carbon dioxide gas. calculate how many moles CO2 gas does it contains?

What defines a mixture? A) A mixture contains different substances that are chemically combined. B) A mixture contains different substances that are not chemically combined and can be broken down into its basic substances through physical means.

How much does 5 gallons of water weigh?

Calculate the percent by mass sulfur in sulfuric acid, h2so4.

4. What electrons are involved in chemical bonding?