Atomic nuclei of almost all elements consist of
a. only neutrons
b. protons and electrons
c. neutrons and electrons
d. only protons
e. protons and neutrons
Ans: e. protons and neutrons
You might also like to view...
Which of the following statements comparing open and globular star clusters is true?
A) Stars in open clusters are relatively young, while stars in globular clusters are very old. B) Open clusters are found both in the disk and the halo of the galaxy, while globular clusters are found only in the halo. C) Globular clusters typically contain a few hundred stars, while open clusters typically contain tens to hundreds of thousands of stars. D) Open clusters contain only main-sequence stars, while globular clusters contain only giants.
According to current science, why didn't oxygen begin to accumulate in the atmosphere for more than a billion years after life appeared on Earth?
A) Early forms of animal life consumed the oxygen released by plants during the first billion years of life on Earth. B) Early life did not release oxygen, and oxygen releasing organisms didn't evolve for a billion years after the earliest life. C) Oxygen was removed from the atmosphere by dissolving in the ocean as quickly as it was released by life. D) Oxygen was removed from the atmosphere by chemical reactions with surface rocks as quickly as it was released by life.
A pencil partially submerged in a glass of water appears broken or offset because of
a. polarization. b. diffraction. c. interference. d. refraction.
One of the products of combustion is water. Why doesn't this water extinguish the combustion?
A) While areas of combustion are being extinguished, new areas are combusting. B) Combustion only produces micro amounts of water. C) The chemical combustion reaction is happening too fast for the water to have an effect on the fire. D) This water is in the gaseous phase and merely floats away from the fire.