Answer:
3.4 × 10
^−
4
Explanation:
Move the decimal so there is one non-zero digit to the left of the decimal point. The number of decimal places you move will be the exponent on the
10
. If the decimal is being moved to the right, the exponent will be negative. If the decimal is being moved to the left, the exponent will be positive.
Answer:
0.05
moles
Explanation:
In a mole of any substance, there exist
6.02⋅1023
units of that substance.
So here, we got:
3.01⋅1022Mg atoms⋅1mol6.02⋅1023M gatoms=0.05mol
Answer:
D. A compound can be separated into two or more elements through a chemical reaction.
Explanation:
By method of elimination, we are going t obtain the correct option.
A. A compound is made up of a single atom.
This is wrong because, a compound can contain more than one atom. An example is H2O
B. A compound is made up of many atoms that are all the same type.
This is wrong because a compound can contain atoms of different elements. An example is H2O. It contains atoms of hydrogen and oxygen.
C. A compound can be separated into two or more elements through physical processes.
This is wrong. H2O being a compound cannot be separated by ordinary physical means.
D. A compound can be separated into two or more elements through a chemical reaction.
This is the correct option.
Water polluting
increased invasive species
overfishing
electricity cuts
loss of homes
