Answer:
- <u>Cadmium has larger atomic radius than sulfur.</u>
Explanation:
Down a period, atomic radii decrease from left to right due to the increase in the number of protons and electrons across a period: when a proton is added the pull of the electrons towards the nucleus is larger, so the size of the atom decreases.
Hence, you can compare the elements that belong to a same period and predict that the atom with lower atomic number (number of protons) will haver larger atomic radius. With that:
- Oxygen and fluorine are in the period 3, being oxygen to the left of fluorine, so oxygen is larger than fluorine.
- Sulfur and chlorine are in the period 4, being sulfur to the left of chlorine, so sulfur is larger than chlorine.
Now see whan happens down a group. Atomic radius increases from top to bottom within a group due to electron shielding. That permits you to compare the size of the elements in a group:
- Fluorine and chlorine are in the same group (17), with chlorine directly below fluorine, so the atomic radius of chlorine is larger than the atomic radius of fluorine.
- Sulfur and oxygen are in the same group (16), with sulfur directlly below oxygen, so sulfur the atomic radius of sulfur is larger than the atocmi radius of oxygen.
So far, you can rank the atomic radius of sulfur, chlorine, fluorine, and oxygen, in increasing order as:
- O < F < Cl < S, concluding that O, F, and Cl have smaller atomic radius than S.
Cadmiun, Cd, is to the left and below sulfur, so both electron shielding (down a group) and increase of the number of protons (down a period) lead to predict the cadmium has a larger atomic radius than sulfur.
Answer:
Methods of soil conservation are listed below.
Explanation:
The major sources of soil erosion include water,wind and tillage. In order to mitigate or prevent soil erosion, some of the following techniques can be implemented:
- <u>Contour Farming: </u>Planting in row patterns that run level around a hill — as opposed to the up and down the slope pattern.This reduces runoffs and consequently water erosion.
- <u>Crop Rotation:</u> This involves planting crops with high residue (e.g corn, small grains, e.t.c) in rotation,as the layer of residue would protect the topsoil.
- <u>Built in structural diversion</u> : Used often for gully control, to regulate flow of water away from the field and through designated desired paths.
- <u>Conservation Tillage</u>: This involves methods such as no-till planting, strip rotary tillage, etc, which do not allow the soil surface to be smooth and bare, but instead covered with crop residue that protects the soil from eroding forces.
Answer:
Beryllium, because it is in period 2 and has four total electrons.
Explanation:
Answer:
C. H2O is the base and H3O+ is the conjugate acid
Explanation:
According to Bronsted-Lowry acid-base theory, an acid is a substance that loses an hydrogen ion or proton (H+) while a base is a substance that gains an hydrogen ion (H+) or proton. Furthermore, this theory states that, the molecule formed when an acid donates its proton is called the CONJUGATE BASE, while the molecule formed when the base accepts proton is called CONJUGATE ACID.
In this question, the following equation is given:
NH4+(aq) + H2O(aq) ⇌NH3(aq) + H3O+ (aq)
Water (H2O) is the base in this equation because according to Bronsted-Lowry acid-base theory, it accepts an hydrogen ion (H+) while hydroxonium ion (H3O+) is the conjugate acid.
Answer:
use chemical equation to that answer
