Hey there
the answers are
A.
and
D. He could spray the fire extinguisher in the opposite direction of the space station
hope this helps
Answer:
Dark matter makes up 85% of the mass of the universe. Dark matter is not directly observable because it doesn't interact with any electromagnetic wave. In the development of the universe, without dark matter, the universe will not function, move or rotate as it does now (this speculation led to the quest to find the anomaly of mass and energy in the known universe, eventually leading to the idealization of dark matter) and will not have enough gravitational force to hold it together. After the big bang,<em> the presence of dark matter and energy ensured that the newly formed universe didn't just float away, rather, it provided enough gravitational force to hold the universe while still allowing it to expand sufficiently</em>.
The development of the universe would have been different without the universe in the sense that the young universe won't have enough mass to hold it together, and the universe would have simply floated apart. The behavior of the universe would have been different from what we observe now, and some physical laws that applies now will not apply to the universe.
<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
Mass of reactants > mass of products
