The apparent effects of the gravity of unseen matter on visible objects
Answer:
Anything not on the periodic table is an element non example! ... So, for a substance to be an element, all of its atoms must have the same number of protons. Examples of elements include hydrogen, lithium, nickel, and radium.
Explanation:
For the first one I think it’s A, and I think the second one is C. Those seem most logical.
Answer:
0.098 moles
Explanation:
Let y represent the number of moles present
1 mole of Ba(OH)₂ contains 2 moles of OH- ions.
Hence, 0.049 moles of Ba(OH)2 contains y moles of OH- ions.
To get the y moles, we then do cross multiplication
1 mole * y mole = 2 moles * 0.049 mole
y mole = 2 * 0.049 / 1
y mole = 0.098 moles of OH- ions.
1 mole of OH- can neutralize 1 mole of H+
Therefore, 0.098 moles of HNO₃ are present.
Answer:
3.86x10^24 molecules
Explanation:
From the question given, the following data were obtained:
Volume of ice = 0.5cup
1 cup = 240mL
0.5cup = 0.5 x 240 = 120mL
Density of ice = 0.9167 g/mL
molar mass of water = 18.015g/mol
First let us calculate the mass of ice. This is illustrated below:
Density = Mass /volume
Mass = Density x volume
Mass = 0.9167 x 120
Mass of ice = 110.004g = Mass of water
From Avogadro's hypothesis, we understood that 1mole of any substance contains 6.02x10^23 molecules. This means that 1mole of water will also contain 6.02x10^23 molecules.
1mole of water = 18.015g
If 1 mole (18.015g) contains 6.02x10^23 molecules,
Therefore, 110.004g of water will contain = (110.004x6.02x10^23)/18.015 = 3.86x10^24 molecules
