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3 years ago

13

For years, surgeons have had great success using _____.

2 answers:

sweet-ann [11.9K]3 years ago

7 0

C artificial heart valves

FrozenT [24]3 years ago

6 0

C the artifical heart

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We want to calculate the concentrations of all species in a 0.58 M Na 2 SO 3 (sodium sulfite) solution. The ionization constants

NeX [460]

Explanation:

Reaction equation is as follows.

$Na_{2}SO_{3}(s) \rightarrow 2Na^{+}(aq) + SO^{2-}_{3}(aq)$

Here, 1 mole of $Na_{2}SO_{3}$ produces 2 moles of cations.

$[Na^{+}] = 2[Na_{2}SO_{3}] = 2 \times 0.58$

= 1.16 M

$[SO^{2-}_{3}] = [Na_{2}SO_{3}]$ = 0.58 M

The sulphite anion will act as a base and react with $H_{2}O$ to form $HSO^{-}_{3}$ and $OH^{-}$ .

As, $K_{b} = \frac{K_{w}}{K_{a_{2}}}$

= $\frac{10^{-14}}{6.3 \times 10^{-8}}$

= $1.59 \times 10^{-7}$

According to the ICE table for the given reaction,

$SO^{2-}_{3} + H_{2}O \rightleftharpoons HSO^{-}_{3} + OH^{-}$

Initial: 0.58 0 0

Change: -x +x +x

Equilibrium: 0.58 - x x x

So,

$K_{b} = \frac{[HSO^{-}_{3}][OH^{-}]}{[SO^{2-}_{3}]}$

$1.59 \times 10^{-7} = \frac{x^{2}}{0.58 - x}$

$x^{2} = 1.59 \times 10^{-7} \times (0.58 - x)$

x = 0.0003 M

So, x = $[HSO^{-}_{3}] = [OH^{-}]$ = 0.0003 M

$[SO^{2-}_{3}]$ = 0.58 - 0.0003

= 0.579 M

Now, we will use $[HSO^{-}_{3}]$ = 0.0003 M

The reaction will be as follows.

$HSO^{2-}_{3} + H_{2}O \rightleftharpoons H_{2}SO_{3} + OH^{-}$

Initial: 0.0003

Equilibrium: 0.0003 - x x x

$K_{b} = \frac{x^{2}}{0.0003 - x}$

$K_{b} = \frac{K_{w}}{K_{a_{1}}}$

= $\frac{10^{-14}}{1.4 \times 10^{-2}}$

= $7.14 \times 10^{-13}$

Therefore, $7.14 \times 10^{-13} = \frac{x^{2}}{0.0003 - x}$

As, x <<<< 0.0003. So, we can neglect x.

Therefore, $x^{2} = 7.14 \times 10^{-13} \times 0.0003$

= $0.00214 \times 10^{-13}$

x = $0.0146 \times 10^{-6}$

x = $[OH^{-}] = [H_{2}SO_{3}]$ = $1.46 \times 10^{-8}$

$[H^{+}] = \frac{10^{-14}}{[OH^{-}]}$

= $\frac{10^{-14}}{0.0003}$

= $3.33 \times 10^{-11}$ M

Thus, we can conclude that the concentration of spectator ion is $3.33 \times 10^{-11}$ M.

5 0

3 years ago

Which of these is a body fossil?<br> A.shrimp burrow B.Plant Imprint C. Claw Print D.dinousaur egg

Alik [6]

Claw print could be it

3 0

3 years ago

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Ammonium perchlorate NH4ClO4 is a powerful solid rocket fuel, used in the Space Shuttle boosters. It decomposes into nitrogen N2

patriot [66]

Answer: 0.055 moles of $O_2$ are produced by the reaction of 0.055 mol of ammonium perchlorate.

Explanation:

The balanced chemical reaction for decomposition of ammonium perchlorate is:

$2NH_4ClO_4\rightarrow N_2+Cl_2+2O_2+4H_2O$

According to stoichiometry :

2 moles of $NH_4ClO_4$ produce = 2 moles of $O_2$

Thus 0.055 moles of $NH_4ClO_4$ will produce = $\frac{2}{2}\times 0.055=0.055moles$ of $O_2$

Thus 0.055 moles of $O_2$ are produced by the reaction of 0.055mol of ammonium perchlorate.

7 0

3 years ago

Hana fills a cup with sandy ocean water. She pours the mixture through a filter. What does she collect that passes through the f

Alisiya [41]

The solution of salt and water

6 0

2 years ago

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Is there DNA in the stucture of prokryotic

azamat

Answer:

i hope this helped

They have no true nucleus as the DNA is not contained within a membrane or separated from the rest of the cell, but is coiled up in a region of the cytoplasm called the nucleoid. Prokaryotic organisms have varying cell shapes.

Explanation:

5 0

3 years ago

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