What is true about 1.0 mol ca and 1.0 mol mg they are equal in mass they contain the same number of atoms they have the same atomic mass their molar masses are equal

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.)

How many moles of sulfur dioxide are produced when 4.38 moles of oxygen completely react with iron (iv) sulfide

Imagine if during the cathode ray experiment, the size of the particles of the ray was the same as the size of the atom forming the cathode. which other model or scientific observation would have also been supported? 1. this would support dalton's postulates that proposed the atoms are indivisible because no small particles are involved. 2. this would support bohr's prediction about electrons moving in orbits having specific energy. 3. this would support bohr's prediction about electrons being randomly scattered around the nucleus in the atom. 4. this would support dalton's postulates that proposed that atoms combine in fixed whole number ratios to form compounds.