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3 years ago

How many significant figures are in 28.6 g

Chemistry

2 answers:

Alex787 [66]3 years ago

8 0

There are no zeros, so all three digits<span> are significant.</span>
<span>b. 3440.</span>

rewona [7]3 years ago

5 0

There are 3 significant figures in 28.6g :)

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Why are more massive atoms smaller?

Varvara68 [4.7K]

As you move from left to right across a period, the number of protons in the nucleus increases. The electrons are thus attracted to the nucleus more<span> strongly, and the atomic radius is </span><span>smaller</span>

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4 years ago

For the reactions below, describe the reactor system and conditions you suggest to maximize the selectivity to make the desired

alexandr1967 [171]

Answer:

hello your question lacks the required reaction pairs below are the missing pairs

Reaction system 1 :

A + B ⇒ D $-r_{1A} = 10exp[-8000K/T]C_{A}C_{B}$

A + B ⇒ U $-r_{2a} = 100exp(-1000K/T)C_{A} ^\frac{1}{2}C_{B} ^\frac{3}{2}$

Reaction system 2

A + B ⇒ D $-r_{1A} = 10exp( -1000K/T)C_{A}C_{B}$

B + D ⇒ U $-r_{2B} = 10^9exp(-10000 K/T) C_{B}C_{D}$

Answer : reaction 1 : description of the reactor system : The desired reaction which is the first reaction possess a higher activation energy and higher temperature is required to kickstart reaction 1

condition to maximize selectivity : To maximize selectivity the concentration of reaction 1 should be higher than that of reaction 2

reaction 2 :

description of reactor system : The desired reaction i.e. reaction 1 has a lower activation energy and lower temperatures is required to kickstart reaction 1

condition to maximize selectivity:

to increase selectivity the concentration of D should be minimal

Explanation:

Reaction system 1 :

A + B ⇒ D $-r_{1A} = 10exp[-8000K/T]C_{A}C_{B}$

A + B ⇒ U $-r_{2a} = 100exp(-1000K/T)C_{A} ^\frac{1}{2}C_{B} ^\frac{3}{2}$

the selectivity of D is represented using the relationship below

$S_{DU} = \frac{-r1A}{-r2A}$

hence SDu = 1/10 * $\frac{exp(-800K/T)}{exp(-1000K/T)} * C_{A} ^{0.5} C_{B} ^{-0.5}$

description of the reactor system : The desired reaction which is the first reaction possess a higher activation energy and higher temperature is required to kickstart reaction 1

condition to maximize selectivity : To maximize selectivity the concentration of reaction 1 should be higher than that of reaction 2

Reaction system 2

A + B ⇒ D $-r_{1A} = 10exp( -1000K/T)C_{A}C_{B}$

B + D ⇒ U $-r_{2B} = 10^9exp(-10000 K/T) C_{B}C_{D}$

selectivity of D

$S_{DU} = \frac{-r1A}{-r2A}$

hence Sdu = $1/10^7 * \frac{exp(-1000K/T)}{exp(-10000K/T)} *\frac{C_{A} }{C_{D} }$

description of reactor system : The desired reaction i.e. reaction 1 has a lower activation energy and lower temperatures is required to kickstart reaction 1

condition to maximize selectivity:

to increase selectivity the concentration of D should be minimal

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4 years ago

What kind of reaction is 2H2O2 2H2O + O2??

coldgirl [10]

Answer: "decomposition reaction" .
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4 years ago

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alex41 [277]

Answer:

D) all of the above

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4 years ago

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Learn more about electronic configuration here:

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2 years ago