Answers:
The average atomic mass will be closer to 7 amu, the average atomic mass of lithium is 6.94 amu and it is the same as the atomic mass on the periodic table.
Explanations:
We can predict that the average atomic mass will be closer to 7 amu because Li-7 has a much higher abundance on earth than Li-6.
To get the average atomic mass using isotopes, we must multiply the mass of each isotope by its natural abundance and then add the products.
(6.0151223 × 0.075) + (7.0160041 × 0.925)
= 0.45 + 6.49
= 6.94 amu
Our calculated average atomic mass is the same as the atomic mass on the periodic table.
D that is the correct answer
Answer:
density.
Explanation:
A cubic centimeter of water weighs 1 gram. Since a cubic centimeter of vegetable oil weighs less than 1 gram, oil will float on water. Corn syrup is more dense than water so 1 cubic centimeter of corn syrup weighs more than 1 gram. Therefore, corn syrup sinks in water.
<span>Measuring with a graduated cylinder is complicated somewhat by a meniscus. A meniscus is the curvature of the surface of the water. Water "sticks" to the walls of the graduated cylinder, but only on the sides and not the middle.
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Answer:
B, C
Explanation:
The atoms or ions with the valid Lewis dot structures are B and C.
In A;
The Lewis structure of the carbon is correct. Each of the four dots represent the four valence electrons.
The nitrogen with one dot on top, left and to the bottom and has a charge of minus 3 is wrong. For it to have a charge of -3 it must have 8 lewis dots ( two on the top, right, bottom and to the left)
The nitrogen with four dots (on top, right, bottom and to the left) is wrong.
In B;
An oxygen has two dots on top and bottom and one dot to the left and to the right. This is correct , the 6 dots represent the valence electrons of oxygen.
In C;
A carbon has two dots on top, right, bottom and to the left and a charge of plus four. This is correct because the charge indicates that it has gained four extra electrons so its valence electrons is now 8.
In D;
An oxygen has two dots on top, left and to the bottom and a charge of minus 2. This is wrong because the lewis dots are incomplete. Two dots are missing.