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:
Calcium sulphate is the right answer for this question.
It is because calcium sulphate helps to obtain the hardness in water. hardness.
The presence of this resource is a main reason for permanent hardness.
Hard drinking water has moderate health benefits, but can pose serious problems for the industrial settings.
Explanation:
1. What is a property of a base? You should N-O-T taste laboratory chemicals!!! I don't know why textbooks emphasize the taste of acids and bases. But that is the answer.
<span>2. In the reaction of aluminum bromide with ionized sodium bromide, which compound is the Lewis acid? </span>
<span>What reaction??? </span>
<span>3 In a neutral solution the [H^+] is ____. </span>
<span>At 25C a solution is said to be neutral when the hydrogen ion concentration is 1.00x10^-7M. </span>
<span>4 With solutions of strong acids and strong bases, the word strong refer to ____. </span>
<span>The strength of electrolytes, including acids and bases, describes the degree to which the substance ionizes. Strong acids and bases ionize completely in water. </span>
<span>5 Which of the following pairs consists of a weak acid and a strong base? </span>
<span>a. sulfuric acid, sodium hydroxide == strong, strong </span>
<span>b.acetic acid, ammonia == weak, weak </span>
<span>c. acetic acid, sodium hydroxide* == weak, strong </span>
<span>d. nitric acid, calcium hydroxide == strong, strong </span>
<span>6. The ionization constant (K^a) of HF is 6.7 x 10^-4. Which of the following is true in a 0.1M solution of this acid? </span>
<span>a. [HF] is greater than [H^+][F^-].* == Yep </span>
<span>b. [HF] is less than [H^+][F^-]. == Nope </span>
<span>c. [HF] is equal to [H^+][F^-]. == if K=1 </span>
<span>d. [HF] is equal to [H^+][F^2-] == nonsense </span>
<span>7. The process of adding a known amount of solution of known concentration to determine the concentration of another solution is called ____. </span>
<span>The process of finding the concentration of an acid or base by neutralizing it with a known concentration of a known volume is a titration.</span>
Answer : The true statements are:
(a) Emulsions are a type of colloid
(b) The particles of a colloid are larger than the particles of a solution
(d) Many colloids scatter light (tyndal effect)
Explanation :
Colloid : It is defined as the solution in which the one substance is insoluble in another solution that means the insoluble substance rotating in the solution.
The particles of a colloid are larger than the particles of a solution.
Colloid do not separate on standing.
Cannot be separated by filtration.
Scatter light (Tyndall effect).
For example :
Milk is considered as a colloid because various substances (fats, proteins etc..) are present in milk which are suspended in a solution.
Suspension : It is a heterogeneous mixture in which some of the particles are settle down in the mixture on standing or over time.
The particles in a suspension are far larger than those of a solution.
Emulsion : It is a mixture of two or more liquids that are normally immiscible.
Emulsions are a type of colloid.
Answer:
He2 molecule contains 4 electrons. Each atom gives 2 electrons in 1s orbitals. This way 2 (1s) orbitals combine to give 2 molecular orbitals viz. ... This indicates that there is no bond formation between 2 HE atoms and hence the He2 molecule does not exist.
Explanation:
