When air is heated up the molecules spread out and move faster, so heat rises because it is less dense than the cooler air around it.
Answer:
D. Nitrogen-14 has 7 electrons, 7 protons, 7 neutrons nitrogen-15 has 7 electrons, 7 protons, and 8 neutrons
Explanation:
In an atom, number of electrons is equal to the number of protons. And the number of neutrons is equal to the difference between the mass number of the atom and the atomic number. For Nitrogen 14, electron is 7, proton is also 7 as number of electrons and number of protons are equal. So, the neutron will be 14-7= 7. For Nitrogen 15, electron number is 7 so proton number will be also 7. Neutron number for nitrogen 15 will be 15-7= 8. That's why the answer is option number 4.
The answer would be: Endometrium.
Answer:
Hydrogen gas has the highest calorific value of 150 KJ/g among all the fuels. So, hydrogen gas is considered to be an extremely good fuel.
Explanation:
Answer:
cell
tissue
organ
system
human organism
Explanation:
unicellular organisms only have one cell since two or more cells form a tissue their level of organization is restricted to cell
cell
two or more cells form a tissue
two or more tissue forms an organ
two or more organs form a system which must work in coordination for efficiency
two or more systems make up a human organism
