A and B

Quasars are extremely distant celestial bodies. Investigators using a special telescope determined that a certain quasar was emitting waves with a frequency of 1.41 x 10^9 Hz. An electromagnetic spectrum is shown. The investigators were most likely using a telescope that detects —

• microwaves

• visible light

• x-rays

• gamma rays

Tags

NGSS.HS-PS4-1

Which statement best describes the location of the sun in the Milky Way galaxy?

• The sun is located in the center of the spiral-shaped galaxy.

• The sun is located off the center of an elliptical-shaped galaxy.

• The sun is located on an arm of a spiral-shaped galaxy.

• The sun is located on an arm of an elliptical-shaped galaxy.

With the use of the Hubble Space Telescope, scientists recently discovered a giant runaway star. It is 90 times larger than the sun and is very hot and blue-white in color. Why does the sun appear to be brighter than this runaway star when viewed from Earth?

• The sun is a different color than the runaway star.

• The sun is older than the runaway star.

• The sun is closer to Earth than the runaway star.

• The sun is made of different elements than the runaway star.

A Hertzsprung-Russell (H-R) diagram is shown. A star that has a luminosity of 10^-2 and a temperature of 20,000 K is most likely a —

• Main sequence

• White dwarf

• Blue giant

• Red giant

The Hertzsprung-Russell diagram shown is divided into four sections. Which section of the diagram includes the coolest, brightest stars?

• Section 1

• Section 2

• Section 3

• Section 4

Tags

NGSS.HS-ESS1-3

What part of the atom determines the identity of an atom?

• Electrons

• Neutrons

• Protons

• Nucleus

Which statement correctly describes the location and charge of the electrons in an atom?

• The electrons are inside the nucleus and have no charge

• The electrons are outside the nucleus and have no charge

• The electrons are inside the nucleus and have a negative charge

• The electrons are outside the nucleus and have a negative charge

How would you describe the nucleus of an atom?

• dense, positively charged

• large, positively charged

• tiny, negatively charged

• dense, negatively charged

At the atomic level, what makes elements reactive?

• having a filled outer level

• exchanging or sharing valence electrons

• having the same number of electrons

• having the same number of protons

A chemist is identifying the elements present in a sample of seawater. What characteristic of an element's atoms always determines the element's identity?

• The number of electrons

• The number of neutrons

• The number of protons

• The number of valence electrons