Answer: last option, what came before the big bang?
Explanation:
The big bang theory states that the universe started as a dense nucleus of matter: a huge amount of matter concentrated in a tiny spot.
This is the conclusion of equations and evidences that prove that the universe has been and continuous to expand: since it has been expanding, there was a moment when it was as small and dense as it is possible.
So, the expansion is the result of violent explosion.
The time during which the expansion has been happening (this is how long ago the big bang occured) has been estimated thanks the the observation of the speed of recesion of the galaxies, but nothing can be told about what came before the bing bang occured.
Answer:
<h3>The answer is 196 g</h3>
Explanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volume
From the question we have
mass = 56 × 3.5
We have the final answer as
<h3>196 g</h3>
Hope this helps you
Answer:
1.94 × 10⁻³
Explanation:
Step 1: Calculate the concentration of H⁺ ions
We will use the definition of pH.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.32 = 4.79 × 10⁻³ M
Step 2: Calculate the acid dissociation constant (Ka) of the acid
For a monoprotic weak acid, whose concentration (Ca) is 0.0118 M, we can use the following expression.
Ka = [H⁺]²/Ca
Ka = (4.79 × 10⁻³)²/0.0118 = 1.94 × 10⁻³
Answer:
Explanation:
Hello,
In this case, the molecular chemical reaction is:
Thus, by considering the ionic species we have:
Wherein the ammonium and bromide ions are spectator ions since nickel (II) phosphate is largely insoluble in water, therefore, the net ionic equation is:
Best regards.
Answer:
0.210 M
Explanation:
<em>A 75.0 mL aliquot of a 1.70 M solution is diluted to a total volume of 278 mL.</em>
In order to find out the resulting concentration (C₂) we will use the dilution rule.
C₁ × V₁ = C₂ × V₂
1.70 M × 75.0 mL = C₂ × 278 mL
C₂ = 0.459 M
<em>A 139 mL portion of that solution is diluted by adding 165 mL of water. What is the final concentration? Assume the volumes are additive.</em>
Since the volumes are additive, the final volume V₂ is 139 mL + 165 mL = 304 mL. Next, we can use the dilution rule.
C₁ × V₁ = C₂ × V₂
0.459 M × 139 mL = C₂ × 304 mL
C₂ = 0.210 M
