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lakkis [162]
2 years ago
11

What are the three types of scientific investigations?

Chemistry
2 answers:
borishaifa [10]2 years ago
6 0
D should be the right answer hope this helps
pashok25 [27]2 years ago
4 0
D.... I think it might be D lol 
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The conversion of methyl isonitrile to acetonitrile in the gas phase at 250 °C CH3CN(g) is first order in CH3NC with a rate cons
nadya68 [22]

Answer: The concentration of CH_3NC will be 1.56\times 10^{-2}M after 416 seconds have passed.

Explanation:

Expression for rate law for first order kinetics is given by:

t=\frac{2.303}{k}\log\frac{a}{a-x}

where,

k = rate constant = 3.00\times 10^{-3}s^{-1}

t = age of sample = ?

a = let initial amount of the reactant = 5.45\times 10^{-2}M

a - x = amount left after decay process = 1.56\times 10^{-2}M

t=\frac{2.303}{3.00\times 10^{-3}}\log\frac{5.45\times 10^{-2}}{1.56\times 10^{-2}}

t=416s

The concentration of CH_3NC will be 1.56\times 10^{-2}M after 416 seconds have passed.

5 0
3 years ago
The compound sodium thiosulfate pentahydrate, Na2S2O3 • 5H2O
Mnenie [13.5K]

The theoretical yield is 204.4 g while the percent yield is 2.57%.

<h3>What is theoretical yield?</h3>

Theoretical yield is the amount of product obtained based on the stoichiometry of the reaction.

S8(s) + 8 Na2SO3(aq) + 40 H2O(l) --->8 Na2S2O3·5 H2O(s)

Number of moles of sulfur =  3.25 g /8(32) = 0.013 moles

Number of moles of sodium sulfite =  13.1 g/126 g/mol = 0.103 moles

Since 1 moles of sulfur reacts with 8 moles of sodium sulfite

0.013 moles reacts with 0.013 moles ×  8 moles /1 mole = 0.104 moles

There is not enough sodium sulfite hence it is the limiting reactant.

1 mole of sodium sulfite yields 8 moles of product

0.103 moles of sodium sulfite yields  0.103 moles × 8 moles /1 mole = 0.824 moles

Mass of product = 0.824 moles × 248 g/mol = 204.4 g

percent yield =  5.26 g /204.4 g × 100/1

= 2.57%

Learn more about percent yield: brainly.com/question/2506978

4 0
2 years ago
Given these reactions, X ( s ) + 1 2 O 2 ( g ) ⟶ XO ( s ) Δ H = − 668.5 k J / m o l XCO 3 ( s ) ⟶ XO ( s ) + CO 2 ( g ) Δ H = +
qwelly [4]

<u>Answer:</u> The \Delta H^o_{rxn} for the reaction is -1052.8 kJ.

<u>Explanation:</u>

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction follows:

X(s)+\frac{1}{2}O_2(g)+CO_2(g)\rightarrow XCO_3(s)      \Delta H^o_{rxn}=?

The intermediate balanced chemical reaction are:

(1) X(s)+\frac{1}{2}O_2(g)\rightarrow XO(s)    \Delta H_1=-668.5kJ

(2) XCO_3(s)\rightarrow XO(s)+CO_2     \Delta H_2=+384.3kJ

The expression for enthalpy of the reaction follows:

\Delta H^o_{rxn}=[1\times \Delta H_1]+[1\times (-\Delta H_2)]

Putting values in above equation, we get:

\Delta H^o_{rxn}=[(1\times (-668.5))+(1\times (-384.3))=-1052.8kJ

Hence, the \Delta H^o_{rxn} for the reaction is -1052.8 kJ.

7 0
3 years ago
Calculate the number of grams in sodium in 7.6g of Na2C6H6O7 (sodium hydrogen citrate) express your answer using two significant
Katen [24]

Answer:

Explanation:

the molecular mass of Na2C6H6O7 =236 g\mole it has a sodium that has 23 g/mole so 7.6 g of Na2C6H6O7 has x of sodium mass

  236 g/mole ⇒  23g/mole

<h2>   7.6 g  ⇒    ˣ    </h2>

7.6 x 23 ÷ 236  = 74.07×10-2 grams of sodium

<h2 />
7 0
2 years ago
Why do you think most lampshades are made of translucent materials instead of transparent materials?
Gala2k [10]

Explanation:

because translucent shades lets the light through easily (gentle diffusion)

6 0
2 years ago
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