<h3>
Answer:</h3>
0.50 mol SiO₂
<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
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
30 g SiO₂ (sand)
<u>Step 2: Identify Conversions</u>
Molar Mass of Si - 28.09 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of SiO₂ - 28.09 + 2(16.00) = 60.09 g/mol
<u>Step 3: Convert</u>
- Set up:
- Multiply/Divide:
<u>Step 4: Check</u>
<em>Follow sig figs and round. We are given 2 sig figs.</em>
0.499251 mol SiO₂ ≈ 0.50 mol SiO₂
Answer:
P-block metals have classic metal characteristics like they are shiny, they are good conductors of heat and electricity, and they lose electrons easily. These metals have high melting points and readily react with nonmetals to form ionic compounds.
Explanation:
Acetic acid is 60.05 grams/mole. In 1 liter of vinegar or 1000 ml there would be 0.046% of acetic acid = 46 ml x 1.005g/ml = 46.23 grams/60.05 grams= 0.77 moles per litre of vinegar.This then would be the concentration of acetic acid in for example 1 liter of vinegar.
Answer:
16 minutes
Explanation:
First, we need to calculate the amount of heat needed to cool the beef stew:
Q = mcΔT
Where <em>m</em> is the mass, <em>c</em> is the heat capacity and <em>ΔT</em> is the variation of the temperature.
Q = 10x4x(40 - 90)
Q = -2000 kJ
So, the beef stew needs to lost 2000 kJ to cool.
With the initial temperature at 90ºC, the rate of cooling(r) will be:
r = 1.955x(90 - 25)
r = 127.075 kJ/min
So, to lose 2000 kJ, will be necessary:
t = Q/r
t = 2000/127.075
t = 16 minutes
