Answer:
1. Which statement correctly describes the classification of chemical reactions into different categories?
-Not all reactions fit into a category, and some reactions can fit into more than one category.
2. In a synthesis reaction, two atoms of sodium (Na) combine with one molecule of chlorine gas (Cl2) to produce sodium chloride (NaCl). How many molecules of sodium chloride are produced?
-Two
3. In the decomposition of water, why is twice as much hydrogen as oxygen formed?
- There are two atoms of hydrogen and one atom of oxygen in a water molecule.
4. Which component is transferred between substances in an oxygen-reduction reaction?
-Electrons
5. In a chemical reaction, substance A transfers electrons to substance B. Which statement is correct?
-Substance B is reduced and acts as the oxidizing agent.
Answer:
A. Soaps react with ions in hard water to create a precipitate.
B. Soaps are both hydrophobic and hydrophilic.
D. Soaps should be weakly alkaline in solution.
Explanation:
A. Hard water contains <u>magnesium and calcium minerals</u> like calcium and magnesium carbonates, sulfates and bicarbonates. As soon as these minerals come in contact with soap their ions like Mg²⁺ & Ca²⁺ form precipitates.
B. Soap are both hydrophilic and hydrophobic. They reason why they exhibit both the properties is really important for their functionality. The hydrophobic part of soap makes interaction with oil/dust particles while the hydrophilic part makes interaction with water. When the cloth is rinsed the dirt/soap particles are removed from the dirty clothes thereby making them clean.
C. Soaps have alkaline pH i.e. more than 7 that is why they have bitter taste.
Answer:
Gas to Solid
Explanation:
A condensation reaction goes from gas to solid
Condensation is a physical change which alters the physical properties of matter particularly the form and state. In a condensation reaction, a gas goes from solid to liquid.
It is the inverse of the sublimation reaction.
- It involves the loss in energy by a gas.
- When gases lose energy, they become pulled together by attractive forces.
- This changes their state to solid with enough loss in energy.
In mineralogy and crystallography, a crystal structure<span>is a unique arrangement of atoms in a </span>crystal. Acrystal structure<span> is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice.
Crystals create a harder more fitting structure so they tend to be a lot stronger than other compounds or elements</span>