1) Carbon-13:
Proton-6 Neutron-7 Electron-6
2)Atomic mass of element X:
(55*10+56*20+57*70)/100=56.6
Answer:
1st answer: A. nitrogen
2nd answer: A. Sodium carbonate
Explanation:
A mineral is a naturally occurring chemical compound,
usually of crystalline form and abiogenic in origin. A mineral has one specific
chemical composition. Coal is not a mineral because it is organic while a
mineral is inorganic that have repeating crystalline structure.