Question | Answer |
Anything that has mass and takes up space is ___. | matter |
A small particle that is the building clock of matter is ___. | atom |
Matter with a composition that is always the same is ___. | substance |
A substance made of only one kind of atom is a ___. | element |
Two or more atoms that are held together by chemical bonds and act as a unit is called ___. | molecule |
A substance mode of two or more elements that are chemically joined in a specific combination is called ___. | compound |
Matter that can vary in composition is called ___. | mixture |
A mixture in which the substance are not evenly mixed is a ___ mixture. | heterogeneous |
A mixture in which two or more substances are evenly mixed, but not bonded together is a ___ mixture. | homogeneous |
The region at the center of an atom that contains most of the mass of the atom is the ___. | nucleus |
A positively charged particle in the nucleus of an atom is the ___. | proton |
An uncharged particle in the nucleus of an atom is the ___. | neutron |
A negatively charged particle that occupies the space in an atom outside the nucleus is the ___ | electron |
___ is the region surrounding an atom's nucleus where one or more electrons are most likely to be found. | electron cloud |
___ is the number of protons in the nucleus of an atom of an element. | atomic number |
One or two more atoms of an element having the same number of protons, but a different number of neutrons is the ___. | isotope |
___ is an atom that has a charge because it has gained or lost electrons. | ion |
The nucleus of an atom contains (protons/electrons) and neutrons. | protons |
The nucleus has a (positive charge/negative charge) and the (least mass/most mass) of the atom. | positive charge: most mass |
An electron is a (positively charged/negatively charged) particle located outside the nucleus. | negatively charged |
The modern model of an atom is called the (electron cloud/nucleus orbit) model. | electron cloud |
Electrons that are close to the nucleus have (more energy/less energy) than electrons that are farther from the nucleus. | more energy |
The atomic number is the number of (protons/neutrons) in the nucleus of an atom of an element. | protons |
Isotopes have the same number of protons but different numbers of (electrons/neutrons). | neutrons |
An ion has a charge because it has gained or lost (protons/electrons). | electrons |
A (positive/negative) ion has more protons than electrons. | positive |
Adding a(n) (proton/electron) to a neutral atom produces a new element. | proton |