Plastic is endothermic because plastic can melt
Answer:
13.4g
Explanation:
we know that:
1 mole = 6.02 × 10²³ atoms
make the unknown number of moles = x
x = 7.1 × 10²² atoms
putting them both together:
1 mole = 6.02 × 10²³ atoms
x = 7.1 × 10²² atoms
Cross multiply:
6.02 × 10²³ x = 7.1 × 10²²
divide both sides by 6.02 × 10²³


we now have the number of moles of Al₂CO₃
to calculate the grams (mass):


add up all of the atomic masses of Al₂CO₃ to calculate relative formula mass:
(27 × 2) + 12 + (16 × 3) = 114
the grams (mass) of Al₂CO₃:

Answer:
The periodic table tells you the atomic number (which tells you the number of protons and electrons). It also includes the mass number, which is the sum of the protons and neutrons in the nucleus of an atom.
They are determined by the length of time it takes for light to travel from the Earth to the desired star
Answer: barbiturates
Explanation: barbiturates is a kind of drug that can produce effects similar to those of alcohol, ranging from mild relaxation to an inability to feel pain, loss of consciousness, and impaired judgment.