Answer:
One mole of a substance is equal to 6.022 × 10²³ units of that substance (atoms, molecules, or ions)
Explanation:
This number is Avogadro's number. The concept of the mole can be used to convert between mass and number of particles. its used to compare very large numbers.
The answer is; Cosmic background radiation is leftover thermal energy from the big bang.
Called the coming microwave background the weak radiation fills the universe more or less uniformly. This radiation is the fossil remnants of the postulated big band at the beginning of the universe. The photos produced at the time continue to travel through the universe growing fainter over time and have fallen in the microwave range of the electromagnetic spectrum now.
Answer:
The correct answer is - 2770000 cm.
Explanation:
1 kilometer = 1000 meter
1 meter = 100 centimeter
1 kilometer = 100*1000 cm
1 km = 100000 cm.
then,
27.7 kilometers = 2.77 × 10^6 centimeters
So, 27.7 kilometers = 27.7 × 100000
= 2.77 × 106 or 2770000 centimeters.