It is given that the charge on potassium is +1 i.e. Potassium is a cation, K⁺
The charge on selenium is given as -2, i.e. selenium is an anion, Se²⁻
The two ions are shown to combine to form a molecule: KXSeY where X and Y correspond to the proportions in which the two atoms combine.
Since the molecule is neutral, the positive and negative charges need to be balanced. This is possible only if 2 units of K⁺ combines with 1 unit of Se²⁻.
Therefore, the formula would be K₂Se
X = 2 and Y = 1
It has 4 valance electrons.
Answer:
1. Democritus - Matter was made of different kinds of things.
2. Bernoulli- Gases are formed from tiny particles so small you can’t see them. The particles are spread out into a certain area and move when people walk through them.
3. Priestley- Substances combine or break apart to create new, different substances.
Explanation:
1. Democritus was a philosopher who because of his immense contribution to atomic theory was regarded as the "FATHER OF SCIENCE". His idea was that matter was made of different kinds of things called which he called ATOMOS meaning ATOM.
2. Daniel Bernoulli was another outstanding mathematician and scientist who played a major part in the kinetic molecular theory of gases via his "HYDRODYNAMICA". His idea, which states that "gases are formed from tiny particles so small you can’t see them. The particles are spread out into a certain area and move when people walk through them"
was based on fluid dynamics.
3. Joseph Priestley is remarkably known for his 1774 discovery of oxygen. His findings that air is a mixture of gases and not just a substance made of one element paved the way for his idea that " Substances combine or break apart to create new, different substances".
Answer:
Ten possibilities for staving off catastrophic climate change ... What can one person, or even one nation, do on their own to slow and reverse climate change? ... could reduce greenhouse gas emissions to safer levels—there are ... mode of transport that does not require anything other than human energy.
Explanation: