1. What is the smallest part of all matter called? (1 point) *
a. Element
b. Atom***
c. Molecule
d. Compound
2. Which of the subatomic particles is negative? (1 point)
a. Nucleus
b. Neutron
c. Proton
d. Electron*****
3. Who provided the first evidence that atoms contain subatomic particles? (2 points) *
a. Thomson****
b. Rutherford
c. Dalton
d. Newton
4. When two fluorine atoms share a pair of electrons, the bond that forms is a(n) _____________. (2 points) *
a. Double bond
b. Polar covalent bond
c. Nonpolar covalent bond***
d. Ionic bond
5. How would you find the number of neutrons in an atom? (2 points) *
a. Atomic number - mass number****
b. Mass number - atomic number
c. Electrons + protons
d. Protons - electrons
6. Isotopes of an element have the same atomic number, but different mass numbers because they have different numbers of ________________. (2 points) *
a. Electrons
b. Protons
c. Neutrons***
d. Subatomic particles
7. Electrons in the first energy level of an atom, (2 points) *
a. Have no energy
b. Have the lowest possible energy****
c. Have the highest possible energy
d. Are unstable
8. An element that is shiny and easily conducts electric currents is called a ________________. (2 points) *
a. Nonmetal
b. Metal****
c. Transition metal
d. Noble gas
9. Elements that have the same number of valence electrons are in the same __________ on the periodic table. (2 points) *
a. Group*****
b. Period
c. Row
d. Section
10. Which list of elements contains only metalloids? (2 points) *
a. Gallium, germanium, and arsenic
b. Silicon and germanium******
c. Aluminum, silicon, and phosphorus
d. Phosphorus and arsenic
11. In the Rutherford experiment, why weren’t all the alpha particles deflected? (3 points) *
a. The particles have a positive charge.
b. The particles were too small.
c. The nucleus was too small compared to the atom as a whole.*****
d. The beam was attracted to a positively charged plate.
12. What does an electron cloud represent? (3 points)
a. The location of electrons around the nucleus*******
b. The location of electrons within the nucleus
c. The location of electrons in the universe
d. The location of the nucleus
5 is not right. The others look OK to me.
Leptons and quarks are the smallest part of all matter soes far as we can tell
1. The smallest part of all matter is called an atom.
2. The subatomic particle that is negative is an electron.
3. The first evidence that atoms contain subatomic particles was provided by Thomson.
4. When two fluorine atoms share a pair of electrons, the bond that forms is a nonpolar covalent bond.
5. To find the number of neutrons in an atom, subtract the atomic number from the mass number.
6. Isotopes of an element have the same atomic number, but different mass numbers because they have different numbers of neutrons.
7. Electrons in the first energy level of an atom have the lowest possible energy.
8. An element that is shiny and easily conducts electric currents is called a metal.
9. Elements that have the same number of valence electrons are in the same group on the periodic table.
10. The list of elements that contains only metalloids is silicon and germanium.
11. In the Rutherford experiment, not all alpha particles were deflected because the nucleus was too small compared to the atom as a whole.
12. An electron cloud represents the location of electrons around the nucleus.
To find the smallest part of all matter, you would need to understand the concepts of atoms, elements, molecules, and compounds.
1. An element is a pure substance that cannot be further broken down into simpler substances. Elements are made up of one type of atom. While atoms are the building blocks of matter, they are not the smallest part.
2. A subatomic particle that has a negative charge is called an electron. Electrons orbit around the nucleus of an atom.
3. The scientist who provided the first evidence that atoms contain subatomic particles is Thomson. J.J. Thomson conducted experiments that led to the discovery of electrons, which proved the existence of subatomic particles within atoms.
4. When two fluorine atoms share a pair of electrons, the bond that forms is a nonpolar covalent bond. Covalent bonds occur when atoms share electrons to achieve a stable electron configuration.
5. To find the number of neutrons in an atom, you can subtract the atomic number from the mass number. The atomic number represents the number of protons in an atom, and the mass number represents the total number of protons and neutrons.
6. Isotopes of an element have the same atomic number but different mass numbers because they have different numbers of neutrons. Neutrons contribute to the mass of an atom but do not affect its atomic number.
7. Electrons in the first energy level of an atom have the lowest possible energy. Energy levels, also known as electron shells or orbitals, are regions around the nucleus where electrons are likely to be found. Electrons in higher energy levels have higher energy.
8. An element that is shiny and easily conducts electric currents is called a metal. Metals generally have high electrical and thermal conductivity and are usually solid at room temperature.
9. Elements that have the same number of valence electrons are in the same group on the periodic table. Valence electrons are the electrons in the outermost energy level of an atom and are responsible for the chemical properties of elements. Groups on the periodic table share similar chemical properties.
10. The list of elements that contains only metalloids is silicon and germanium. Metalloids are elements that have properties intermediate between metals and nonmetals.
11. In the Rutherford experiment, not all the alpha particles were deflected because the nucleus was too small compared to the atom as a whole. Rutherford discovered that the positive charge and most of the mass of an atom is concentrated in a small, dense region called the nucleus. Most of the atom is empty space.
12. An electron cloud represents the location of electrons around the nucleus. It is a region of probability where electrons are most likely to be found. The cloud is a visual representation of the electron's uncertain position due to its wave-like nature.