Science and Maths Quiz ChallengeOnline version Test your knowledge on science and mathematics with this fun quiz! by Amish Patodiya 1 What is the chemical symbol for water? a O2 b NaCl c CO2 d H2O 2 17x8=? a 138 b 136 c 140 d 134 3 smallest 5-digit no. - biggest 5 digit no. a 9999 b 1 c 8900 d 89999 4 how many bones does a human baby have? a 206 b 100 c 300 d 500 5 What is the most abundant gas in Earth's atmosphere? a Hydrogen b Oxygen c Nitrogen d Carbon Dioxide