How many valance electron do atoms need to be stable

Brian is a healthy young man. He has been training with his teammates for a 50-yard dash for months. However, even with practice, he cannot run fast enough to qualify. What is the most likely reason that Brian can't qualify?

Johnnie's father worked his entire career in the automotive manufacturing industry in Michigan. When Johnnie entered the workforce, the auto industry was in decline, so he instead found a professional career in the booming information technology

The average distance of the earth from the sun is about 1.5 * 10^8 km. Assume that the earth's orbit around the sun is circular and that the sun is at the origin of your coordinate system.

Earth moves in an elliptical orbit with the sun at one of the foci. The length of half of the major axis is 149,598,000 kilometers, and the eccentricity is 0.0167.

A mountain climber of mass 60.0 kg slips and falls a distance of 4.00 m, at which time he reaches the end of his elastic safety rope. The rope then stretches an additional 2.00 m before the climber comes to rest.

a the average distance from the Sun to Pluto is approximately 6.10 x 1 0 ^9. how long does it take light from the sun to reach Pluto?

A 25kg object moves from left to right at a speed of 30km/h. What net force is required to keep this object moving in a straight line at constant speed

Ganymede is one of the many moons of jupiter. it is nearly a sperical in shape. it is larger than the planet mercury and slightly smaller than the planet mars.

Which of the following statements about two carts rolling on a track and experiencing a completely inelastic collision is TRUE? a. The kinetic energy of the system is conserved to good approximation. b.

If element X has 17 protons, how many electrons does it have?