Answer:When a substance undergoes a chemical change some of the chemical changes can be reversed with a chemical change.
Explanation:
A chemical change changes all of the element but some chemical changes but very few can be changed back to its original substance only with a chemical change.
<h3>
Answer:</h3>
91.2 g Mn
<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>
- Reading a Periodic Table
- 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>
[Given] 1.00 × 10²⁴ atoms Mn
<u>Step 2: Identify Conversions</u>
Avogadro's Numer
[PT] Molar Mass of Mn - 54.94 g/mol
<u>Step 3: Convert</u>
- [DA] Set up:

- [DA] Multiply/Divide [Cancel out units]:

<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 3 sig figs.</em>
91.2321 g Mn ≈ 91.2 g Mn
Answer:
6.2 calories
Explanation:
Data Given:
change in temperature = 20 °C
specific heat of gold = 0.031 calories/gram °C
mass of gold = 10.0 grams
Amount of Heat = ?
Solution:
Formula used
Q = Cs.m.ΔT
Where:
Q = amount of heat
Cs = specific heat of gold = 0.031 calories/gram °C
m = mass
ΔT = Change in temperature
Put values in above equation
Q = 0.031 calories/gram °C x 10.0 g x 20 °C
Q = 6.2 calories
So option A is correct = 6.2 calories
The data indicates a direct relationship with a positive slope.
<h3>What is direct relationship?</h3>
Direct relationship is a type of relation in which if one factor increases the other will also increases and vice versa. This data represents direct relationship because the increase occur in one value causes increase of another value so we can conclude that the data indicates a direct relationship with a positive slope.
Learn more about relationship here: brainly.com/question/25862883