Questions

9 P in SS  is a short form for 9 Planets i  Solar System.

There are many more of this kind. Some of them are:

1. 7 C in a R        -    7 Colours in a Rainbow

2.  90 D in a R A   -    90 Degrees in a Right Angle

3.  52 W in a Y     -    52 Weeks in a Year

4.  5 C in an OF

5.  12 S of the Z

A Yardstick has three feet used for measuring but no toes.

Racecar and Civic are the two vehicles which spelled the same forwards an backwards.

50.0 mL 0.0500 M calcium hydroxide, Ca(OH)2 (aq) has the highest pH value.

Sodium hydroxide and Calcium hydroxide are strong bases so they completely ionize in solution. Because they ionize at the same rate, and Calcium hydroxide has the higher pH calculated, then Calcium hydroxide, in fact, has the highest pH.

Nitric acid is a strong acid, so it completely ionizes in water. Whilst nitrous acid is a weak acid. Therefore, the nitric acid solution has the LOWEST ph.

As clear from the diagram, AD2=122+92=152

 So, AD = 15