B. Most species that have lived on earth are now extinct. Ap3x
Answer:
liver and esophagus.
Explanation:
Kidneys are part of the endocrine system, trachea and bronchi are part of the respiratory system
The answer is 40.
We can solve this by finding out the number of protons, and neutrons. Atomic number of an element means the number of protons in that element. So, the atom has 30 protons if the atomic number is 30.
On the other hand, mass number is the total number of protons and neutrons, but not electrons, because they're too light comparing to the other 2. Therefore, we can simply solve the number of neutrons in the atom by subtracting the number of protons from the mass number. 70 - 30 = 40.
Therfore, the number of neutrons is 40.
Answer:
The final state of the substance is a gas.
The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Let's consider the phase diagram for Argon (not to scale).
<em>A sample of argon is initially at a pressure of 49.6 atm and a temperature of 101.4 K. The pressure on the sample is reduced to 0.680 atm at a constant temperature of 101.4 K. Which of the following are true? Choose all that apply </em>
<em>The final state of the substance is a gas.</em> TRUE. At 0.680 atm and 101.4 K, the substance is a gas.
<em>The gas initially present will solidify.</em> FALSE. Initially, Ar is present as a liquid.
<em>The final state of the substance is a solid.</em> FALSE.
<em>The sample is initially a liquid. One or more phase changes will occur.</em> TRUE. The sample is initially liquid and only one phase change will occur.