What makes up all stars?
Choices
a heavy elements
b plasma
c hydrogen gas
d steam
b plasma
The International Astronomical Union (IAU) defines a constellation by its
Choices
a boundary
b brightest star
c star pattern
d Greek name
a boundary
Which statements are TRUE about energy and matter in stars? Select the three correct answers
Choices
a Some matter is converted into energy within stars.
b All energy is converted into matter in stars.
c Only energy is conserved within stars.
d Energy in stars causes the fusion of light elements.
e Energy and matter are both conserved in stars.
f Only matter is conserved within stars.
The three correct statements are:
a) Some matter is converted into energy within stars.
d) Energy in stars causes the fusion of light elements.
e) Energy and matter are both conserved in stars.
The correct answer is:
b) plasma
Stars are primarily made up of plasma, which is often referred to as the fourth state of matter. Plasma is a high-energy, ionized gas composed of positively charged ions and free-moving electrons. These charged particles generate intense heat and light in the core of the star.
The correct answer is b) plasma.
To understand why plasma is the correct answer, let's briefly explain what plasma is and how it is related to the composition of stars.
Plasma is often referred to as the fourth state of matter, alongside solids, liquids, and gases. It is a gas-like state in which atoms become ionized, meaning they lose or gain electrons, resulting in charged particles. In plasma, the positively charged ions and negatively charged electrons coexist.
Stars are massive celestial objects composed mainly of hydrogen gas. Throughout the majority of a star's life, hydrogen atoms undergo a process called nuclear fusion. This occurs in the star's core, where extreme temperatures and pressures cause hydrogen atoms to collide and fuse together, forming helium. This fusion reaction releases an enormous amount of energy in the form of heat and light, which is what makes stars shine.
During this fusion process, the hydrogen atoms are heated to such high temperatures that they become plasma. As the fusion reaction releases energy, the plasma in a star's core generates the immense heat and pressure necessary to sustain the fusion process.
Therefore, the correct answer is b) plasma, as it is the state of matter that results from the fusion of hydrogen atoms in the cores of stars.