Answer:
The Earth formed billions of years after the Universe formed
Explanation:
The "universe" is said to have been formed <em>billions of year ago</em> through an explosion. This was called the <em>"Big Bang Theory." </em>This lead to the<u> expansion of the universe</u> owing to its high temperature and density. After which, the universe cooled down. Galaxies and stars were then formed. Some of the stars died due to explosion, which then led to the <u>creation of planets</u>. Such formation of the planets happened around <u>4.5 billion years ago.</u> This is <em>9.3 billions of years later</em> than the universe was formed<em> (13.8 billions of years ago)</em>. So, this explains the answer.
Basis: 1 L of the substance.
(1.202 g/mL) x (1000 mL) = 1202 g
mass solute = (1202 g) x 0.2 = 240.2 g
mass solvent = 1202 g x 0.8 = 961.6 g
moles KI = (240.2 g) x (1 mole / 166 g) = 1.45 moles
moles water = (961.6 g) x (1 mole / 18 g) = 53.42 moles
1. Molality = moles solute / kg solvent
= 1.45 moles / 0.9616 kg = 1.5 m
2. Molarity = moles solute / L solution
= 1.45 moles / 1 L solution = 1.45 M
3. molar mass = mole solute / total moles
= 1.45 moles / (1.45 moles + 53.42 moles) = 0.0264
Answer:
B. A body at rest will stay at rest until it is acted upon by another object
Explanation:
Newton's first law states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.
Answer: 2.26x 10²⁴ atoms C
Explanation: To get the number of atoms,
First we convert mass of C to moles
45g C x 1mole C / 12 g C
= 3.75 moles C
Cancel g of C
Next convert moles of C to atoms using Avogadro's Number.
3.75 moles C x 6.022x10²³ atoms C / 1 mole C
Cancel out the units of moles C.
= 2.26x 10²⁴ atoms of C
