Answer:
easy
Explanation:
In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.
I mean this is pretty obvious it's D. life expectancy is sort of close but not really. B is close too but it's not it bc that's not what health is. you could be over weight and not be sick and it still isn't healthy. and C isn't close at all. hope this helps, have an amazing day :)
<h3>
Answer:</h3>
4.7 × 10²⁴ atoms Li
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Atomic Structure</u>
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<u>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
7.8 mol Li
<u>Step 2: Identify Conversions</u>
Avogadro's Number
<u>Step 3: Convert</u>
- Set up:
- Multiply/Divide:
<u>Step 4: Check</u>
<em>We are told to round to 2 sig figs. Follow sig fig rules and round.</em>
4.69716 × 10²⁴ atoms Li ≈ 4.7 × 10²⁴ atoms Li
Answer:
A₅B₄
Explanation:
Since we have one atom of element A at the center of each face of the unit cell, since the unit cell is a cubic cell, we have 6 faces. Since the atom on the face of the unit cell is shared with another cell, we have half of it in the unit cell is shared So, the number of atoms per face is 1/2 atom/face × 6 faces = 4 atoms on the faces of the unit cell.
Also, we have 1 atom at each corner of the cubic unit cell. Since there are 8 corner in the cubic unit cell. Also, each atom at the corner is shared with 8 unit cells, so we have 1/8 atom per corner. So, the number of atoms per unit cell is 1/8 atom/corner × 8 corners = 1 atoms at the corners of the unit cell.
So, in total we have 4 + 1 = 5 atoms of element A in the unit cell.
Also, there are 4 atoms of element B in the unit cell.
So, the ratio of atoms of element A to element B is 5 : 4.
A:B = 5:4
So, the empirical formula of the compound containing elements A and B is A₅B₄