speed equals wavelength times frequency so
.7 x 500 = 350
Covalent bond is a type of chemical bond which is formed as a result of sharing of electron pairs among the elements that are involved. The structure of the covalent bond is affected by the electronegativity of the elements involved. The molecules joined by covalent bond range in size from very small to very large polymers. There are different types of structures for covalent substances, these include: macromolecular substances, molecular substances and giant covalent structures. Strong bonds hold individual molecules together but there are negligible forces of attraction among them.
<span>The law of conservation of energy states that energy can neither be created nor destroyed - it can only be converted from one form to another. It basically means that energy can't just appear, but has to be converted from existing energy; for example, the chemical energy in petrol is turned into electrical energy to power a car.Remember the total energy of universe is constant,,and no more energy can be drawn from out if we collect all universe's energy at a single point(its the big bang energy splitted during </span>
Answer:
1,2,3
Explanation:
Heat gain implies that heat is absorbed by the system in order to make the stated phase transition possible.
Before a liquid changes to gas, intermolecular forces in the liquid are broken by energy supplied as heat.
Also, transition from solid to liquid requires energy to break intermolecular bonds.
Finally, sublimation requires input of energy in the form of heat.