1.
What number on the scale represents a neutral level?
Correct Answer
B. 7
Explanation
A neutral level on the scale is represented by the number 7. This is because a scale typically ranges from 0 to 14, with 0 being the most acidic and 14 being the most alkaline. A value of 7 indicates a neutral pH level, which means it is neither acidic nor alkaline.
2.
And speaking about neutral, what color represents neutral on the pH scale?
Correct Answer
C. Green
Explanation
Green represents neutral on the pH scale. The pH scale measures the acidity or alkalinity of a substance, with values ranging from 0 to 14. A pH of 7 is considered neutral, indicating a balance between acidity and alkalinity. Green is often associated with balance and harmony, making it an appropriate color to represent neutrality on the pH scale. Blue is typically associated with alkaline substances, while red is associated with acidic substances. Yellow does not have a direct association with neutrality on the pH scale.
3.
What is the range covered by the pH scale?
Correct Answer
A. 0 - 14
Explanation
The pH scale is a measure of the acidity or alkalinity of a solution. It ranges from 0 to 14, with 0 being the most acidic, 7 being neutral, and 14 being the most alkaline. This scale allows us to quantify the concentration of hydrogen ions in a solution, where lower values indicate higher acidity and higher values indicate higher alkalinity. Therefore, the correct answer is 0 - 14.
4.
Where would you expect to find an acidic result on the scale?
Correct Answer
A. Towards the lower numbers
Explanation
The lower numbers on the scale indicate a higher concentration of hydrogen ions, which is characteristic of acidic substances. Therefore, an acidic result would be expected towards the lower numbers on the scale.
5.
Which of these numbers best represents an alkaline solution?
Correct Answer
D. 13
Explanation
An alkaline solution is a solution with a pH value greater than 7. The numbers given represent pH values, and the number 13 is the highest among them. Therefore, 13 best represents an alkaline solution as it indicates a high concentration of hydroxide ions and a low concentration of hydrogen ions, making the solution basic or alkaline.
6.
Which of these colors would suggest the most acidic solution?
Correct Answer
B. Red
Explanation
Red is the color that would suggest the most acidic solution. In the context of pH indicators, red is often associated with low pH values, indicating high acidity. This is because red is commonly used to represent the color change that occurs when an acid is present. Therefore, in this question, red is the most appropriate color to suggest the most acidic solution.
7.
Which of these colors would suggest the most alkaline solution?
Correct Answer
D. Blue
Explanation
Blue is the color that would suggest the most alkaline solution. In the pH scale, alkaline solutions have a higher pH value, typically above 7. Blue is commonly associated with higher pH levels and alkalinity. It is often used to indicate basic or alkaline substances, such as in litmus paper tests. Therefore, the color blue would be the most suitable choice to suggest the presence of an alkaline solution.
8.
Which century did the pH scale develop and come into use?
Correct Answer
A. 20th Century
Explanation
The pH scale was developed and came into use in the 20th century. This scale measures the acidity or alkalinity of a substance, with a pH of 7 being neutral, values below 7 indicating acidity, and values above 7 indicating alkalinity. The concept of pH was introduced by Danish chemist Søren Peder Lauritz Sørensen in 1909, and it quickly gained recognition and became a widely used method for measuring the acidity of solutions. Therefore, the correct answer is the 20th century.
9.
PH scale full form is
Correct Answer
C. Potential of Hydrogen
Explanation
The correct answer is "Potential of Hydrogen." The pH scale is a measure of the concentration of hydrogen ions in a solution. It indicates the acidity or alkalinity of a substance. The term "potential" refers to the ability of hydrogen ions to donate or accept protons, which determines the level of acidity or alkalinity. Therefore, "Potential of Hydrogen" accurately represents the purpose and meaning of the pH scale.
10.
A solution with a pH of 4.6 would be
Correct Answer
A. Acidic
Explanation
A solution with a pH of 4.6 is considered acidic because it falls below the neutral pH of 7. pH is a measure of the concentration of hydrogen ions in a solution, and a lower pH indicates a higher concentration of hydrogen ions. A pH of 4.6 suggests a higher acidity level, making the solution acidic.