A
What is the formula for penta magnesium tri chloride
Mg5Cl3
A chemical bond characterized by the sharing of one or more electron pairs between two atoms in a molecule is called a(n) ___.
covalent bond
Which are the three steps of the scientific method?
hypothesizing, observing and experimenting
What is the maximum number of valence electrons an atom may have?
8
What gives you the number of protons in an atom?
atomic number
What type of bond results from the sharing of four electrons?
double bond
A formula in which nonbonding electrons are shown as dots around atoms and bonds are shown as lines or dots between atoms is ____________.
Lewis structure
An atom of a particular element is distinguished from atoms of other elements by the number of ___ in the nucleus. (what gives the identity of the element)
protons
What is the molar mass of H2PO4
96.98
How do you call the elements in the same row of the periodic table?
period
What type of substance consists of two or more elements chemically combined?
compound
Which of the following is not evidence that a chemical change has occurred?
change in color, formation of gas, precipitation or water freezing
water freezing
What is the pH of a solution HCl = 0.0778
1.11
If a strip of blue litmus paper turns red when dipped into a solution, the pH must be ___. (number range)
less than 7
Classify the following reactions:
HClO3 + KOH --> H2O + KClO3
Ag + NaCl --> AgCl + Na
double displacement
single displacement
What is defined as how close to the exact value a measurement is?
accuracy
The elements lithium, sodium, potassium, and cesium belong to the group of elements known as the __ metals.
alkali
How do you call the elements in the same columns of the periodic table?
family
The elements helium, argon, and xenon belong to the family of elements known as the ___.
noble gases
How do you express the following number in regular form: 6.5 x 10 -3
0.0065
What substance produces hydroxide ions?
Base
Which are the three subatomic particles, their charges and location?
proton - inside nucleus - positive
neutron - inside nucleus - neutral
electron - outside nucleus - negative
How particles behave in the three states of matter?
solid they can't barely move, liquid they move but not enough and gas they are randomly moving.
When writing a chemical reaction, the __ are on the left and the __ are on the right.
reactants, products
Give the name for the following elements:
Mg Hg Ca
Na Ag Si
Mg- magnesium
Na- sodium
Hg- mercury
Ag- silver
Ca- calcium
Si- silicon