True. Each contour line on a topographic map represent a certain elevation; the closer they are, the steeper the surface is. All points on a contour line are the same elevation.
Answer:
Some of the chemicals used to preserve food and give it color are sodium nitrate, sodium benzoate, and propionate
Explanation:
Answer: Option (B) is the correct answer.
Explanation:
- An ionic bond is formed by the sharing of electrons between two chemically combining atoms.
In an ionic bond, there occurs attraction between oppositely charged ions due to which there occurs strong forces of attraction between them. Therefore, ionic bonds are the strongest bonds.
- A polar covalent bond is formed due to unequal sharing of electrons between the combining atoms.
For example,
is a polar covalent compound. Partial opposite charges tend to develop on the atoms of a polar covalent compound.
- A non-polar covalent bond is formed due to equal sharing of electrons between the combining atoms.
For example,
is a non-polar covalent molecule. No partial charges will be there on the atoms of a non-polar covalent molecule.
- A hydrogen bond is defined as the bond formed between a hydrogen atom and an electronegative atom.
For example, in HCl compound there occurs hydrogen bonding.
In this type of bond, dipole-dipole attractive interactions tend to take place. And, strength of hydrogen bonds is very weak.
Thus, we can conclude that given bond types are arranged in order of increasing strength as follows.
Hydrogen bonds < non-polar covalent bonds < polar covalent bonds < ionic bonds
Oxygen gas produced : 0.7 g
<h3>Further explanation</h3>
Given
10.0 grams HgO
9.3 grams Hg
Required
Oxygen gas produced
Solution
Reaction⇒Decomposition
2HgO(s)⇒2Hg(l)+O₂(g)
Conservation of mass applies to a closed system, where the masses before and after the reaction are the same
mass of reactants = mass of products
mass HgO = mass Hg + mass O₂
10 g = 9.3 g + mass O₂
mass O₂ = 0.7 g