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4 years ago

Question 1 of 10

Chemistry

1 answer:

Natalka [10]4 years ago

5 0

Answer:

Explanation:

A- incorrect, not in alphabetical order

B- incorrect, symbol for salt in NA not SA

C- correct

D- incorrect, not based on discovery

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Which one is a Synthesis reaction?

sveta [45]

Answer:

the second one is synthesis reaction

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3 years ago

If the mass of an object increases, how is the force of gravity effected?<br><br> PLSSSSSSS

neonofarm [45]

Pretty sure the force of gravity increases as the object does.

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2 years ago

Each Excedrin tablet contains 250 mg aspirin (ACE), 250 mg of acetaminophen (ACE), and 65 mg of caffeine (CAF). Calculate the th

yawa3891 [41]

Answer:

a) 37.04% b) 37.04% c) 9.63%

Explanation:

The theoretical percent recovery (Tr), is the total percentage of each compound in the sample. Depending on the technique used to recovery the compounds, the percent recovery will be less than the theoretical, because no technique is 100% efficient.

So, to calculate the theoretical, it will be the mass of the compound divided by the mass of the sample multiplied by 100%.

a) Tr = (250 mg)/(675 mg) * 100%

Tr = 37.04%

b) Tr = (250 mg)/(675 mg) * 100%

Tr = 37.04%

c) Tr = (65 mg)/(675 mg) * 100%

Tr = 9.63%

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4 years ago

On a class trip to the coast, you and your lab partner find a rock in the spot marked in red on the diagram. You show your teach

NNADVOKAT [17]

Cause it’s is the same

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3 years ago

Read 2 more answers

The rate constant of a certain reaction is known to obey the Arrhenius equation, and to have an activation energy Ea = 71.0kJ/mo

aleksandrvk [35]

Explanation:

Relation between temperature and activation energy according to Arrhenius equation is as follows.

k = $A exp^{\frac{-E_{a}}{RT}}$

where, k = rate constant

A = pre-exponential factor

$E_{a}$ = activation energy

R = gas constant

T = temperature in kelvin

Also,

$ln (\frac{k_{2}}{k_{1}}) = (\frac{-E_{a}}{R}) \times (\frac{1}{T_{2}} - \frac{1}{T_{2}})$

$T_{1}$ = $244^{o}C$ = (244 + 273) K = 517.15 K

$T_{2}$ = $324^{o}C$ = (597.15 + 273) K = 597.15 K

$k_{1}$ = 6.7 $M^{-1} s^{-1}$ , $k_{2}$ = ?

R = 8.314 J/mol K

$E_{a}$ = 71.0 kJ/mol = 71000 J/mol

Putting the given values into the above formula as follows.

$ln (\frac{k_{2}}{6.7}) = (\frac{-71000}{8.314} \times (\frac{1}{597.15} - \frac{1}{517.15})$

= 2.2123

$\frac{k_{2}}{6.7} = exp(2.2123)$

= 9.1364

$k_{2} = 61 M^{-1}s^{-1}$

Thus, we can conclude that rate constant of this reaction is $61 M^{-1}s^{-1}$ .

3 0

3 years ago