Download C-3 Atoms: The building blocks of matter Study guide Name Circle

C-3 Atoms: The building blocks of matter
Study guide
Name
Circle the correct answer in each statement.
1. According to the law of conservation of mass, the mass of the reactants is equal to/less than the sum of the
masses of the products.
2. The principles of atomic theory recognized today were conceived by: Avogadro/Dalton .
3. According to Dalton's atomic theory, atoms can be divided/of each element are identical in size, mass, and other
properties.
4. The concept in Dalton's atomic theory that has been modified is
composed of atoms.
5. Experiments with cathode rays led to the discovery of the
atoms cannot be divided/all matter is
proton/electron.
6. Whose series of experiments identified the nucleus of the atom?
7. In Rutherford's experiments, most of the particles
Rutherford/ Chadwick
bounced back/passed through the foil.
8. Because most particles fired at metal foil passed straight through, Rutherford concluded that atoms were mostly
empty space/electrons formed the nucleus.
9. Rutherford's experiments led him to conclude that atoms contain massive central regions that have a positive
charge/a negative charge.
10. A nuclear particle that has about the same mass as a proton, but with no electrical charge, is called a
neutron/electron.
11. An atom is electrically neutral because
and electrons are equal.
neutrons balance the protons and electrons/the numbers of protons
12. Most of the volume of an atom is occupied by the electrons/protons.
13. The radius of an atom extends to the outer edge of the
electrons.
region occupied by the neutrons/region occupied by the
14. Isotopes are atoms of the same element that have different
15. All isotopes of hydrogen contain
numbers of protons/masses.
one proton/ one neutron.
16. The atomic number of oxygen, 8, indicates that there are eight
atom/oxygen nuclides.
protons in the nucleus of an oxygen
17. The total number of protons and neutrons in the nucleus of an atom is its
18. All atoms of the same element have the same
atomic number/mass number.
atomic mass/atomic number.
19. An aluminum isotope consists of 13 protons, 13 electrons, and 14 neutrons. Its mass number is 13/27.
20. Chlorine has atomic number 17 and mass number 35. It has
protons, 35 electrons, and 17 neutrons.
17 protons, 17 electrons, and 18 neutrons/ 35
21. Phosphorus-33 (atomic number 15) contains 18 neutrons/ 18 protons.
22. Neon-22 contains 12 neutrons. It also contains
12 protons/10 protons.
23. The number of atoms in 1 mol of carbon is 6.022 x 10 22/ 6.022 x 1023.
24. The number of atoms in a mole of any pure substance is called its atomic number/ Avogadro's number.
25. The mass of 1 mol of Chromium (atomic mass 51.996 amu) is 198 g/ 51.996 g.
26. The mass of 2.0 mol of oxygen atoms (atomic mass 16.00 amu) is
16 g/ 32 g.
27. The mass of a sample containing 3.5 mol of silicon atoms (atomic mass 28.0855 amu) is approximately
72 g /98 g.
28. The mass of 5.000 mol of cesium (atomic mass 132.9 amu) is 664.5 g / 6.022 x 1023g.
Use dimensional analysis to show your work for each of the following problems.
29. How many atoms are present in 6.00 mol of chlorine atoms?
30. Determine the mass in grams of 4.00 mol of oxygen. The molar mass of oxygen is 16.00 g/mol.
31. Determine the mass in grams of 10.0 mol of bromine. The molar mass of bromine is 79.90 g/mol.
32. Determine the number of moles of helium in 20.0 g of helium. The molar mass of helium is 4.00 g/mol.
33. Determine the number of moles in 100. g of carbon. The molar mass of carbon is 12.01 g/mol.
34. Calculate the mass in grams of 9.00 mol of potassium (molar mass 39.10 g/mol).
35. Calculate the number of atoms in 10.0 g of sulfur ( molar mass 32.07 g/mol).