Unit 1 Test Review: Atoms, Elements, Compounds, Molecules and the Periodic Table
What particles are in the nucleus of an atom What particles are in the nucleus of an atom? (Hint: It’s labeled in the picture to the right!) Answer: Protons and neutrons! What particle has a negative charge? What about positive? Neutral??? Answer: Protons have a POSITIVE charge, electrons have a NEGATIVE charge, while neutrons are NEUTRAL.
The Atomic Number also represents what two particles in the atom? Answer: Protons and electrons! How do you calculate the number of neutrons that are in this sodium atom??? Answer: Atomic Mass- protons = neutrons 4 – 2 = 2 neutrons Atomic Number Symbol Element Atomic Mass
PERIODS 1-7 GROUPS 1-18 What are the rows in the periodic table called? Answer: PERIODS! What are the columns called in the periodic table? Answer: GROUPS!
Out of all the elements, would a metal or noble gas be more reactive??? Answer: METALS, noble gases WILL NOT react with any other elements! Metalloids have what kinds of properties??? Answer: METALS and NONMETALS, that’s why you find them in between the stairstep on the periodic table! By looking at your periodic table, most elements are classified as what???? Answer: METALS!
Silver, gold and platinum are all found in the middle of the periodic table, by looking at your periodic table, what kind of metals are these??? Answer: Transition metals! These metals are very malleable (easy to shape) and from the picture you can see that they are very shiny and another characteristic they all share is that they are GREAT conductors of electricity.
Elements that have dull surfaces and can’t conduct electricity well are called??? Answer: Nonmetal elements
All the examples above are molecules, but only those in the second row are also compounds. A compound is a substance formed by the chemical combination of two or more atoms of different elements, that have different properties than the elements that make them up. *Do you know which part of the atom combines to form these compounds? Answer: Electrons
What atom is pictured and how do you know? Answer: Nitrogen, because there’s 7 electrons which is the same number as the atomic number for Nitrogen.
What atom is pictured and how do you know? Answer: Lithium, same as before the electron number is the same as the atomic number, 3! Protons in red are also 3!
What element is this and how do you know? Answer: Oxygen! Count the electrons (blue) or the protons (red) and you get a count of 8! Oxygen’s atomic number is also 8!
Which elements are found in all silicates, (Mineral Group) ? ANSWER: Silicon and Oxygen How do you know? ANSWER: Chemical formula! Si= Silicon O= Oxygen Which compound contains sulfur (S)? ANSWER: Galena, Pyrite, and Sphalerite How do you know? ANSWER: Chemical formula! S= sulfur
Which element in Gypsum is also the same in Quartz? ANSWER: Oxygen How did you know? ANSWER: Quartz has 2 atoms of oxygen and Gypsum has 5 atoms of oxygen. The only element that is the same in the compound of each element.
What is the ratio of hygrogen atoms to oxygen atoms in the compound with the chemical formula H2O? ANSWER: 2:1
What is a subscript? ANSWER: The small number attached to an element that shows how many atoms are in that element. The chemical formula for vinegar is CH3 COOH. The subscript tells you that vinegar has how many atoms of C (carbon), H(Hydrogen) and how many atoms of O (Oxygen)? ANSWER: 2 Atoms of Carbon 4 Atoms of Hydrogen 2 Atoms of Oxygen
CELEBRATION! WE ARE DONE!!!!