Answer:
Explanation:
A chemical property describes the ability of a substance to undergo a specific chemical change.
A chemical reaction is a process that occurs when one or more substances are changed into one or more new substances.
Differences
Chemical properties are properties that can be observed or measured when a substance undergoes a chemical change.
Physical properties are properties that can be observed without bringing a chemical change.
Another one
chemical properties; can be used to predict how substances react.
chemical changes; It is mostly used in identifying or describing the substance.
7 valence electrons in an atom
Answer:
The Earth formed billions of years after the Universe formed
Explanation:
The "universe" is said to have been formed <em>billions of year ago</em> through an explosion. This was called the <em>"Big Bang Theory." </em>This lead to the<u> expansion of the universe</u> owing to its high temperature and density. After which, the universe cooled down. Galaxies and stars were then formed. Some of the stars died due to explosion, which then led to the <u>creation of planets</u>. Such formation of the planets happened around <u>4.5 billion years ago.</u> This is <em>9.3 billions of years later</em> than the universe was formed<em> (13.8 billions of years ago)</em>. So, this explains the answer.
Largest to smallest: barium, calcium, selenium, oxygen
