Radioactive decay of 40k atoms in an igneous rock has resulted in a radio of 25 percent 40k atoms to 75 percent 40Ar and 40Ca atoms. How many years old is this rock

How does the atomic radius change from top to bottom in Groups 1 and 2?

What new characteristic did John Dalton add to the model of the atom? An atom is a round, solid mass. An atom has a massive, positive center. An atom is made up of smaller particles. An atom can join with other kinds of atoms.

Which is the best example of the law of conservation of energy? A) A basketball stops bouncing because its energy disappears. B) A rolling skateboard slows down because some of its kinetic energy changes to heat.

The energy stored in gasoline is A chemical energy B electromagnetic energy C mechanical energy D nuclear energy

10. A 5.0 g pellet is placed in the barrel of a toy gun and is propelled by a spring of force constant 50. N/m. The spring is compressed 20. cm and then released. Calculate the maximum velocity of the pellet when shot horizontally.

A solid metal ball and a hollow plastic ball of the same external radius are released from rest in a large vacuum chamber. When each has fallen 1 m, they both have the same?

Juan is interested in finding out whether hummingbirds are attracted to some flowers more than others. In what order should Juan perform the steps of his experiment?

Will make Brainlest! <3 Metals are considered to be good conductors of heat. How do the specific heat values indicate this?

Which example identifies a change in motion that produces acceleration? choices are: 1. a speed skater moving at a constant speed on a straight track 2. a ball moving at a constant speed around a circular track 3.

Which of the following diagnostic procedures uses ultrasound?