Chemistry - Elements & Compounds Flashcards
What is a compound?
A compound is a made from two or more elements chemically bonded together.
What places an element in the periodic table?
Its atomic number (the number of protons it has).
What is a mixture?
A mixture of two or more chemical substances that are not chemically bonded.
Is Copper Sulphate an element or a compound?
A compound (it contains more than one type of atom)
Which letters show an element?
E, F and H
Which letters show a mixture?
B, C and G
Which letters show only 3 molecules
D, E and I (Remember: a molecule is a group of atoms bonded together)
How many Hydrogens (H) are there on the left side of the equation?
4
How many molecules of Oxygen (O2) are there on the left side of the equation?
2
How many different elements are there in this equation?
4 : Cu, Ag, N and O. Remember the symbols for chemical elements always start with a capital letter.
How many Nitrogens (N) are there on the left side of the equation?
2
How many Oxygens (O) are there on the right side of the equation?
6 : The number outside the brackets means that you have that many times what is inside the brackets. So 2x3 = 6
What is the mass number?
The number of nucleons (protons and neutrons) in an atom
What is the atomic number?
The number of protons in an atoms. This is also the number of electrons for the atom.
Which element shown has a mass number of 4?
Helium (He) : Remember the mass number is always the bigger number!
How many protons and neutrons does Oxygen (O) have?
Protons: 8
Neutrons: 8
How many protons, neutrons and electrons does Argon (Ar) have?
Protons: 18
Electrons: 18
Neutrons: 22
Protons: 3
Electrons: 3
Neutrons: 4
