Answer:
Both are chemical changes.
Explanation:
They are chemical changes because when when you melt the sugar to make caramel a new substance is formed. The same with cookies. You don't start out with cookies, you start out with dough. And then when you cook the dough a new substance is formed which is the cookies.
Answer:
P2N5
Explanation:
you have to plus it 2 times
Answer:
A space station
Explanation:
A space station provides an avenue for scientist to orbit the space and carryout scientific findings. Most space stations are usually controlled under agreement between different countries. The international space station is one such example.
A rover is usually a robotic device that has been pre-programmed and equipped with state of the art devices to carryout explorations on their own.
Most space observations are usually powerful telescopes on the earth surface that monitors events in space.
A satellite is a body that orbits another.
Answer:
6.022 × 10²³ molecules of B₂H₆
Explanation:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
B₂H₆ molecules:
21.63 g = one mole of B₂H₆= 6.022 × 10²³ molecules of B₂H₆
