Chemistry Test Flashcards
(29 cards)
What is the purpose of writing correctly balanced chemical equations?
To ensure the same number of atoms of each element are present before and after a reaction.
What is the Law of Conservation of Mass?
In a chemical reaction, the same number of atoms of each element must be present before and after the reaction.
What is the role of coefficients in balancing chemical equations?
They are added in front of compounds to ensure equal numbers of atoms before and after the reaction.
How do you denote the products and reactants in a chemical equation?
Reactants are written on the left side of the arrow, and products on the right side.
What happens to an atom when it gains or loses electrons?
It becomes an ion, having a charge due to the difference in the number of protons and electrons.
What is a cation?
A positive ion.
What is an anion?
A negative ion.
What is the charge of a fluorine atom that gains one electron?
-1.
What is the charge of a beryllium atom that loses two electrons?
+2.
What is the formula for sodium chloride?
NaCl.
What is the naming convention for ionic compounds?
The metal is named first, and the non-metal’s name is altered from –ine to –ide.
What is a polyatomic ion?
An ion made up of more than one atom.
Give an example of a common polyatomic ion and its charge.
Hydroxide (OH) with a charge of -1.
What is covalent bonding?
The sharing of valence electrons between non-metal atoms.
What is the procedure for naming covalent compounds?
The first element is named first, and the second element’s name ends in ‘ide’; prefixes indicate the number of atoms.
What are the prefixes used in naming covalent compounds?
- mono * di * tri * tetra * penta * hexa.
What is required for a substance to conduct electricity?
Freely moving charged particles.
Why can’t ionic solids conduct electricity?
The charged ions are held in fixed positions.
What allows metals to be malleable and ductile?
Delocalised electrons that can move freely within the lattice.
What is an alloy?
A mix of different metal atoms combined.
What happens to ionic compounds when manipulated?
They shatter due to the repulsion of like charges.
What is the electron configuration for magnesium (Mg)?
1s² 2s² 2p⁶ 3s².
What is the electron configuration for chlorine (Cl)?
1s² 2s² 2p⁶ 3s² 3p⁵.
Complete the sentence: Noble gases are unreactive because they have a _______.
full outer shell.
