<h3><u>Answer;</u></h3>
When hydrogen is covalently bonded to an electronegative atom
<h3><u>Explanation;</u></h3>
- Hydrogen bonding is a special type of dipole-dipole attraction between molecules. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom.
- Highly electronegative atoms attract shared electrons more strongly than hydrogen does, resulting in a slight positive charge on the hydrogen atom. The slightly positive hydrogen atom is then attracted to another electronegative atom, forming a hydrogen bond.
Answer:
Most metals have <u>luster</u> which means they <u>reflect</u> light
Explanation:
When light, which is made up of energetic photons, comes in contact with the surface of a metal, it is absorbed due to the corresponding energy gaps present between the metal orbital. The absorbed photons results in the raising of the energy levels of electrons within an atom of the metal which later drop back to a lower energy level and re-emit the photons which can now be observed as the metallic luster.
The chemical formula : X₃Y₂
<h3>Further explanation </h3>
The noble gas element is a stable class of elements. The noble gas element is monatomic. Stability of noble gases is caused by an electron configuration that has a stable configuration of 8 (has 8 valence electrons) except He with a duplet configuration (has 2 valence electrons)
Other elements that do not yet have electron configurations such as noble gases will try to achieve their stability by forming bonds between elements.
This is generally called the octet rule
X has 2 valence electrons.to achieve stability, element X will release 2 electrons to form X²⁺
Y has 5 valence electrons, to achieve stability, the element Y will attract/ add electrons to form Y³⁻
The two compounds will form a compound with the charges crossed : X₃Y₂
Answer: Its the 2nd one
Explanation: A straight horizontal line on a speed-time graph means that speed is constant. It is not changing over time. A straight line does not mean that the object is not moving! This graph shows increasing speed.
Theory - an idea to explain something, or a set of guiding principles.
hypothesis - an unproven theory or statement.
fact - something that is true or something that has occurred or has been proven correct.
^^ those are just dictionary definitions but you didn’t include anything to match em with