A 500-g SAMPLE OF A METAL REQUIRES 20.25 kJ TO CHANGE ITS TEMPERATURE FROM 25 C TO ITS MELTING TEMPERATURE, 300 C. WHAT IS THE SPECIFIC HEAT OF THIS METAL?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Select the correct answer a modure consists of glucose and water. what is the percent composition of glucose in the mixture if it contains 1.3 moles of glucose (cho total mass of the mature is 276 grams? ) and the a 1775

Which reason best explains why metals are malleable? a)because they have delocalized electrons b)because they have localized electrons c)because they have ionic bonds d)because they have rigid bonds