# Riddles 11

Riddle 1: What kind of room has no doors or windows? Riddle 2: What kind of tree can you carry in your hand? Riddle 3: Which word in the dictionary is spelled incorrectly? Riddle 4: If you have me, you want to share me. If you share me, you haven’t got me. What am I? Read more about Riddles 11[…]

# First order and first degree differential equations and their geometrical interpretations

A first order and first degree differential equation involves the independent variable x (say), dependent variable y (say) so, it can be put in any one of the following forms: dy/ dx = f(x, y) or f (x, y) = 0, or f(x, y) dx + g(x, y)dy = 0 Where f(x, y) and g(x, Read more about First order and first degree differential equations and their geometrical interpretations[…]

# Diazonium Salts

The diazonium salts have the general formula RN⁺₂X⁻ where R stands for an aryl group and X– ion may be Cl⁻, Br⁻, HSO⁻₄, BF⁻₄ etc. Primary aliphatic amines form highly unstable alkyldiazonium salts. Primary aromatic amines form arenediazonium salts which are stable for a short time in solution at low temperatures (273 – 278 K). Read more about Diazonium Salts[…]

# Riddle 10

Riddle – 1: A car has to carry an important person across the desert. There is no petrol station in the desert and the car has space only for enough petrol to get it half way across the desert. There are also other identical cars that can transfer their petrol into one another. How can Read more about Riddle 10[…]

# Number Puzzle 4

1. Which number replaces the question mark?Answer: 10 Explanation: Working in columns, the sum of the numbers in each column equals 23. 2. Which number replaces the question mark? Answer: 7 Explanation: In each square, multiply the top and bottom numbers together to give a 2 digit result, and put the letters with the numerical values Read more about Number Puzzle 4[…]

# Number Puzzle 4

1. Which number replaces the question mark?2. Which number replaces the question mark?3. Which number replaces the question mark? 4. Which number replaces the question mark?5. Which number replaces the question mark? Share Tweet View Email Print Follow