Ask question

Ask question

All categories

3 years ago

10

38.25 grams of silicon is combined with 14.33 grams of nitrogen gas. How many grams of silicon nitride can be formed if nitrogen

is the limiting reactant?
3Si + 2N2 yields Si3N4

1 answer:

zhuklara [117]3 years ago

6 0

3Si + 2N2 --> Si3N4 (as given)

n(Si) = m/MM = 38.25/28.085 = 1.3619 mol
n(N2) = 14.33/2*14.007 = 0.5115 mol

Therefore, N2 is limiting and Si is in excess
The molar ratio of 2N2:Si3N4 is 2:1
So, 0.0575 mol of silicon nitride is formed (dividing 0.5115 by 2)

m of silicon nitride= n*mm = 0.0575*140.283 = 8.06627... g
= 8.066g (4 significant figures)

(hopefully it is right, but double check in case i did something wrong) :)

You might be interested in

HELP ASAP! Chemical reactions involving liquids only will be influenced by ALL of the following EXCEPT: a) temperature of the sy

Rom4ik [11]

<span>Chemical reactions involving only liquids will be influenced by ALL of the following EXCEPT: </span><span><span>c) size of reactant particles d) pressure of the system.

</span>Reason:
1) As per Arrhenius theory, rate of chemical reactions is influence by temperature. Mathematically it is expressed as: k = A exp(-Ea/RT)
</span>where, k = rate constant, A = collision frequency, Ea = activation energy, T = temp. From above relation, it can be seen that, chemical reactions involving only liquids will be influenced temperature.

2) Also, if know that, rates of chemical reactions is mathematically expressed as: $Rate = [A]^{x} B^{y}....$ ,
where A, B, .. are the reactants.
From above relation, it can be seen that, chemical reactions involving only liquids will be influenced concentration i.e. number of particle.

3) However, since all the reactant and catalyst used (if any) is in liquid state, particle size of same will not influence the reaction.

4) Also, since there are no gas-phase reactant, pressure will not affect the reaction.

8 0

3 years ago

WORTH 20 POINTS Confirmation bias is where a scientist may change the data to support a certain bias.

Orlov [11]

Answer:

True

Explanation:

Confirmation Bias is the tendency to look for information that supports, rather than rejects, one’s preconceptions, typically by interpreting evidence to confirm existing beliefs while rejecting or ignoring any conflicting data

8 0

3 years ago

Compare the density of the ocean crust and the continental crust. If they were to collide, predict which one would push under th

uysha [10]

Answer:

The difference between the density of the ocean crust and the continental crust is the fact that the ocean crust is denser than the continental crust. Meaning, the continental crust is likely to push over the oceanic crust considering it has less dense.

Explanation:

I hope this helps, the last time I learned this was in 5th grade and I am i currently in the 11th grade....

5 0

3 years ago

It is important that the United States move with all deliberate speed to develop and get into usage alternative fuels that will

Charra [1.4K]

Answer:

A. Solar, wind, hydro, nuclear, tidal, and biomass are renewable resources

B. Oil, coal, and natural gasses are the fossil fuels that are nonrenewable resources

C. It is important to move from nonrenewable to renewable because nonrenewable resources will run out and they also create greenhouse gases that hurt the enviroment and cause global warming. Renewable resources are cleaner and either don't run out, or replenish fast enough to not run out

3 0

3 years ago

Use the data given below to construct a Born-Haber cycle to determine the second ionization energy of Ca. Δ H°(kJ) Ca(s)→Ca(g) 1

Drupady [299]

Answer : The value of second ionization energy of Ca is 1010 kJ.

Explanation :

The formation of calcium oxide is,

$Ca(s)+\frac{1}{2}O_2(g)\overset{\Delta H_f}\rightarrow CaO(s)$

$\Delta H_f^o$ = enthalpy of formation of calcium oxide = -635 kJ

The steps involved in the born-Haber cycle for the formation of $CaO$ :

(1) Conversion of solid calcium into gaseous calcium atoms.

$Ca(s)\overset{\Delta H_s}\rightarrow Ca(g)$

$\Delta H_s$ = sublimation energy of calcium = 193 kJ

(2) Conversion of gaseous calcium atoms into gaseous calcium ions.

$Ca(g)\overset{\Delta H_I_1}\rightarrow Ca^{+1}(g)$

$\Delta H_I_1$ = first ionization energy of calcium = 590 kJ

(3) Conversion of gaseous calcium ion into gaseous calcium ions.

$Ca^{+1}(g)\overset{\Delta H_I_2}\rightarrow Ca^{+2}(g)$

$\Delta H_I_2$ = second ionization energy of calcium = ?

(4) Conversion of molecular gaseous oxygen into gaseous oxygen atoms.

$O_2(g)\overset{\Delta H_D}\rightarrow OI(g)$

$\frac{1}{2}O_2(g)\overset{\Delta H_D}\rightarrow O(g)$

$\Delta H_D$ = dissociation energy of oxygen = $\frac{498}{2}=249kJ$

(5) Conversion of gaseous oxygen atoms into gaseous oxygen ions.

$O(g)\overset{\Delta H_E_1}\rightarrow O^-(g)$

$\Delta H_E_1$ = first electron affinity energy of oxygen = -141 kJ

(6) Conversion of gaseous oxygen ion into gaseous oxygen ions.

$O^-(g)\overset{\Delta H_E_2}\rightarrow O^{2-}(g)$

$\Delta H_E_2$ = second electron affinity energy of oxygen = 878 kJ

(7) Conversion of gaseous cations and gaseous anion into solid calcium oxide.

$Ca^{2+}(g)+O^{2-}(g)\overset{\Delta H_L}\rightarrow CaO(s)$

$\Delta H_L$ = lattice energy of calcium oxide = -3414 kJ

To calculate the overall energy from the born-Haber cycle, the equation used will be:

$\Delta H_f^o=\Delta H_s+\Delta H_I_1+\Delta H_I_2+\Delta H_D+\Delta H_E_1+\Delta H_E_2+\Delta H_L$

Now put all the given values in this equation, we get:

$-635kJ=193kJ+590kJ+\Delta H_I_2+249kJ+(-141kJ)+878kJ+(-3414kJ)$

$\Delta H_I_2=1010kJ$

Therefore, the value of second ionization energy of Ca is 1010 kJ.

6 0

3 years ago