Answer:
B) K2X
Explanation:
In an uncharged compound, the total oxidation state must be zero. The oxidation state of the calcium is +2, thus we get the following formula, where x is the oxidation state of the polyatomic ion X:

Also, it is known that potassium has an oxidation state of +1. Since the new compound also has a total oxidation state equal to zero, we get the following equation, where k is the number of K atoms:

That's how it is found that the compumd consists of 2 K+ ions and one X ion.
Answer:
Our atmosphere is a mixture of gases that surround Earth. It is kept in place by the pull of Earth's gravity. If Earth was a much smaller planet, like Mercury or Pluto, its gravity would be to weak to hold a large atmosphere.
Explanation:
Answer:
A they share two covalent bonds
The correct answer is C. It was based on the thoughts of an early philosopher.
Explanation:
An atom is a basic and smallest unit that composes matter and that determine the properties of elements. Regarding the development of ideas related to atoms these did not begin in science but in philosophy; indeed the first person that proposed matter or elements were composed of certain smaller units was the philosophers Leucippus and his pupil Democritus in Ancient Greece, who stated atoms were eternal, infinite and defined the qualities of an object, idea that was supported by other Greek philosophers. But it was not until 16th and 17th centuries after the Middle Ages that the term re-emerged and until the 19th century it was officially proposed and there were experiments by scientists that later became a theory. Therefore, the development of the earliest idea about attoms differs from later work of scientists is that the earliest idea was based on the thoughts of an early philosopher.
<span>
The substance that needs more energy to undergo an increase of 25°C will
have a higher specific heat, because energy depends directly on
specific heat.
Q = cm∆T
where c = specific heat of the substance,
m = mass
∆T = temperature difference </span>