A rapid release of stored up energy
Answer:
A piece of gold foil was hit with alpha particles, which have a positive charge. Most alpha particles went right through. This showed that the gold atoms were mostly empty space. Some particles had their paths bent at large angles. A few even bounced backward. The only way this would happen was if the atom had a small, heavy region of positive charge inside it.
Pseudo-science is not considered real science because it is not testable.
Answer: Option A
<u>Explanation:</u>
Pseudoscience primarily includes beliefs, theories or practices that are somehow incompatible with the scientific facts. The pseudoscience can’t be tested on the basis of science.
Let’s take an example of astrology. Some people believe that stars and other celestial bodies draw a significant impact on their life i.e. Good or bad thing it's just because their stars are working either in a positive or negative manner.
But, this belief doesn’t have any well-proved or authentic background over which the whole concept can rely on. Hence, pseudoscience is not taken as a real science as a lack of strong proves.
Explanation:
When there occurs sharing of electrons between two chemically combining atoms then it forms a covalent bond. Generally, a covalent bond is formed between two non-metals.
An ionic bond is defined as the bond formed due to transfer of one or more number of electrons from one atom to another. An ionic bond is always formed between a metal and a non-metal.
Every atom of an element will have orbitals in which electrons are found. These orbitals are known as energy level.
A molecule is defined as the smallest particle present in a substance or atom.
A metallic bond is formed due to mobile valence electrons shared by positive nuclei in a metallic crystal.
Thus, we can conclude that given statements are correctly matched as follows.
1). a chemical bond formed by the electrostatic attraction between ions - ionic bond
2). a chemical bond formed by two electrons that are shared between two atoms - covalent bond
3). the orbitals of an atom where electrons are found - energy level
4). the smallest particle of a covalently bonded substance - molecule
5). a bond characteristic of metals in which mobile valence electrons are shared among positive nuclei in the metallic crystal - metallic bond
IF magnesium sulfide reacts with oxygen in the air it will produce
magnesium oxide + sulfur (IV) oxide
<u><em>explanation</em></u>
magnesium sulfide burn in oxygen to produce magnesium oxide and sulfur (iv) oxide according to the equation below
2MgS +3O2 →2MgO +2SO2
that is 2 moles of MgS react with 3 moles of O2 to produce 2 moles of MgO and 2 moles of SO2