Which of the following elements are in the same period in the periodic table?
a) li & ne
b) h & li
c) li & mg
d) ne & mg

Ahydrogen atom has 1 electron. how many bonds can hydrogen form? a) 1 b) 2 c) 3 d) 4 e) 5

Apiece of metal with a length of 1.42 cm was measured using four different instruments. which of the following measurements is the most accurate?

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?