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3 years ago

Since the new oceanic crust is created at the mid-ocean ridges, then the Earth is getting bigger.

Chemistry

1 answer:

Svet_ta [14]3 years ago

7 0

Answer:

False

Explanation:

It is true that new crust is being created at the mid-oceanic ridges, but this does not make the Earth any bigger despite the the growth of oceanic crusts in these regions.

The reason that Earth does not get bigger is because the same plates that are being created at the divergent plate boundaries are recycled into the mantle at the subduction zones. Because of this, the surface area of the Earth remains the same.

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In guinea pigs, black fur is the dominant trait. If a white guinea pig mates with a guinea pig that is heterozygous for its blac

Anon25 [30]

The answer is C, since the black pig is heterozygous, it makes the majority black due to its dominant trait, but about 1 in 5 will be white

5 0

3 years ago

20cm of 0.09M solution of H2SO4. requires 30cm of NaOH for complete neutralization. Calculate the

kirill115 [55]

Answer:

Choice A: approximately $0.12\; \rm M$ .

Explanation:

Note that the unit of concentration, $\rm M$ , typically refers to moles per liter (that is: $1\; \rm M = 1\; \rm mol\cdot L^{-1}$ .)

On the other hand, the volume of the two solutions in this question are apparently given in $\rm cm^3$ , which is the same as $\rm mL$ (that is: $1\; \rm cm^{3} = 1\; \rm mL$ .) Convert the unit of volume to liters:

$V(\mathrm{H_2SO_4}) = 20\; \rm cm^{3} = 20 \times 10^{-3}\; \rm L = 0.02\; \rm L$ .
$V(\mathrm{NaOH}) = 30\; \rm cm^{3} = 30 \times 10^{-3}\; \rm L = 0.03\; \rm L$ .

Calculate the number of moles of $\rm H_2SO_4$ formula units in that $0.02\; \rm L$ of the $0.09\; \rm M$ solution:

$\begin{aligned}n(\mathrm{H_2SO_4}) &= c(\mathrm{H_2SO_4}) \cdot V(\mathrm{H_2SO_4})\\ &= 0.02 \; \rm L \times 0.09 \; \rm mol\cdot L^{-1} = 0.0018\; \rm mol \end{aligned}$ .

Note that $\rm H_2SO_4$ (sulfuric acid) is a diprotic acid. When one mole of $\rm H_2SO_4$ completely dissolves in water, two moles of $\rm H^{+}$ ions will be released.

On the other hand, $\rm NaOH$ (sodium hydroxide) is a monoprotic base. When one mole of $\rm NaOH$ formula units completely dissolve in water, only one mole of $\rm OH^{-}$ ions will be released.

$\rm H^{+}$ ions and $\rm OH^{-}$ ions neutralize each other at a one-to-one ratio. Therefore, when one mole of the diprotic acid $\rm H_2SO_4$ dissolves in water completely, it will take two moles of $\rm OH^{-}$ to neutralize that two moles of $\rm H^{+}$ produced. On the other hand, two moles formula units of the monoprotic base $\rm NaOH$ will be required to produce that two moles of $\rm OH^{-}$ . Therefore, $\rm NaOH$ and $\rm H_2SO_4$ formula units would neutralize each other at a two-to-one ratio.

$\rm H_2SO_4 + 2\; NaOH \to Na_2SO_4 + 2\; H_2O$ .

$\displaystyle \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})} = \frac{2}{1} = 2$ .

Previous calculations show that $0.0018\; \rm mol$ of $\rm H_2SO_4$ was produced. Calculate the number of moles of $\rm NaOH$ formula units required to neutralize that

$\begin{aligned}n(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})}\cdot n(\mathrm{H_2SO_4}) \\&= 2 \times 0.0018\; \rm mol = 0.0036\; \rm mol\end{aligned}$ .

Calculate the concentration of a $0.03\; \rm L$ solution that contains exactly $0.0036\; \rm mol$ of $\rm NaOH$ formula units:

$\begin{aligned}c(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{V(\mathrm{NaOH})} = \frac{0.0036\; \rm mol}{0.03\; \rm L} = 0.12\; \rm mol \cdot L^{-1}\end{aligned}$ .

3 0

3 years ago

Is buoyancy a physical or chemical property?

gizmo_the_mogwai [7]

Buoyancy is considered a physical property. It is a type of physical property because it is related to the density and weight of the item, which are both physical.

7 0

2 years ago

what is the pH of a solution that has a hydronium ion concentration 100 times greater than a solution with a pH of 4

Anna71 [15]

Answer:

Explanation:

First, find the hydronium ion concentration of the solution with a pH of 4.

[H₃O⁺] = 10^-pH

[H₃O⁺] = 10⁻⁴

[H₃O⁺] = 1 × 10⁻⁴

Next, multiple the hydronium ion concentration by 100 to find the hydronium ion concentration of the new solution.

[H₃O⁺] = 1.0 × 10⁻⁴ × 100 = 0.01

Lastly, find the pH.

pH = -log [H₃O⁺]

pH = -log (0.01)

pH = 2

The pH of a solution that has a hydronium ion concentration 100 times greater than a solution with a pH of 4 is 2.

Hope this helps.

4 0

3 years ago

15. The starting diol for this molecule is

victus00 [196]

<h2>Answer with explanation </h2>

<h3><em>The starting diol for this molecule is :-</em></h3><h3><em>The starting diol for this molecule is :-D) ethan-1,2-diol.</em></h3>

<em>Hope </em><em>my </em><em>answer </em><em>is</em><em> helpful</em><em> to</em><em> you</em><em> </em><em>☺️</em>

3 0

3 years ago