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Science-Atoms Sect.1
Question | Answer |
---|---|
What is a nucleus? | It is the very small center core of an atom |
What are protons? | Positively charged. Found in the nucleus. |
What are neutrons? | No charge. Found in the nucleus. |
What are electrons? | They move rapidly around the nucleus and have a negative charge. |
What is an atomic number? | The number of protons in a nucleus. |
What are isotopes? | Atoms with the same number of protons and a different number of neutrons. |
What is a mass number? | The sum of the protons and neutrons in the nucleus of an atom. |
What could a model be? | A model could be a diagram, a mental picture, a mathematical statement, or an object that helps explain ideas about the natural world. |
What are the three main particles in an atom? | Protons, neutrons and electrons. |
How do the particles of an atom differ in electric charge? | Protons have positive charge. Neutrons have no charge and electrons have a negative charge. |
Why do atoms have no electric charge even though most of their particles have charges? | Each atom has equal numbers of positively charged protons and negatively charged electrons. They equal themselves out. |
How do you know how many electrons are in an atom? | Since electrons are equal to protons, look at the atomic number. The atomic number tells how many protons are in an atom. |