Which one of the ff is correct about Acids?

What do melting, evaporation, and sublimation have in common?

kvv77 [185]

Explanation:

Sublimation describes a solid turning directly into a gas. Melting, on the other hand, occurs when a solid turns into a liquid. Water can, under the right circumstances, sublimate, though it usually melts at temperatures above 0 degrees Celsius or 32 degrees Fahrenheit. Carbon dioxide (CO2), however, is very different. The conditions that determine whether CO2 melts or sublimates are both temperature and atmospheric pressure.

8 0

3 years ago

Calculate how many grams of sodium azide (NaN3) are needed to inflate a 25.0 × 25.0 × 20.0 cm bag to a pressure of 1.35 atm at a

Luden [163]

Answer : The mass of $NaN_3$ at temperature $20^oC$ 28.47 g.

The mass of $NaN_3$ at temperature $10^oC$ 29.51 g.

Solution : Given,

Pressure of gas = 1.35 atm

Temperature of gas = $20^oC=273+20=293K$ $(0^oC=273K)$

Volume of gas = $25\times 25\times 20cm=12500cm^3=12.5L$ $(1L=1000cm^3)$

Molar mass of $NaN_3$ = 65 g/mole

Part 1 : First we have to calculate the moles of gas at temperature $20^oC$ . The gas produced in the given reaction is $N_2$ .

Using ideal gas equation,

$PV=nRT$

where,

P = pressure of the gas

V = volume of the gas

T = temperature of the gas

n = number of moles of gas

R = Gas constant = 0.0821 Latm/moleK

Now put all the given values in this formula, we get

$(1.35atm)\times (12.5L)=n\times (0.0821Latm/moleK)\times (293K)$

By rearranging the terms, we get the value of 'n'

$n=0.7015moles$

The moles of $N_2$ = 0.7015 moles

The given balanced reaction is,

$20NaN_3(s)+6SiO_2(s)+4KNO_3(s)\rightarrow 32N_2(g)+5Na_4SiO_4(s)+K_4SiO_4(s)$

As, 32 moles of $N_2$ produced from 20 moles of $NaN_3$

So, 0.7015 moles of $N_2$ produced from $\frac{20}{32}\times 0.7015=0.438$ moles of $NaN_3$

Now we have to calculate the mass of $NaN_3$ .

$\text{ Mass of }NaN_3=\text{ Moles of }NaN_3\times \text{ Molar mass of }NaN_3$

$\text{ Mass of }NaN_3=(0.438moles)\times (65g/mole)=28.47g$

Therefore, the mass of $NaN_3$ needed are 28.47 g.

Part 2 : We have to calculate the moles of gas at temperature $10^oC$ and same volume & pressure.

Using ideal gas equation,

$PV=nRT$

Now put all the given values in this formula, we get

$(1.35atm)\times (12.5L)=n\times (0.0821Latm/moleK)\times (283K)$

By rearranging the terms, we get the value of 'n'

$n=0.726moles$

The moles of $N_2$ = 0.726 moles

The given balanced reaction is,

$20NaN_3(s)+6SiO_2(s)+4KNO_3(s)\rightarrow 32N_2(g)+5Na_4SiO_4(s)+K_4SiO_4(s)$

As, 32 moles of $N_2$ produced from 20 moles of $NaN_3$

So, 0.726 moles of $N_2$ produced from $\frac{20}{32}\times 0.726=0.454$ moles of $NaN_3$

Now we have to calculate the mass of $NaN_3$ .

$\text{ Mass of }NaN_3=\text{ Moles of }NaN_3\times \text{ Molar mass of }NaN_3$

$\text{ Mass of }NaN_3=(0.454moles)\times (65g/mole)=29.51g$

Therefore, the mass of $NaN_3$ needed are 29.51 g.

7 0

3 years ago

Name the type of reaction: 8 Fe + S8 → 8 FeS

Hoochie [10]

Answer:

combined nation

Explanation:

it is combination reaction.

6 0

3 years ago

A certain shade of blue has a frequency of 7.18 × 1014 Hz. What is the energy of exactly one photon of this light?

AysviL [449]

I'm assuming you meant 10^(14) instead of 1014
if so, then the energy of one photon will be be 4.76×10^(-19) Joules

4 0

3 years ago

Neon atom can exist freely in mature but sodium atom can not,why

andrew-mc [135]

Answer:-

Neon is a noble gas. Neon with an electronic configuration of 2,8 has 8 electrons in it's outermost shell or valence shell.

According to the Octet theory if an element has eight electrons in it's valence shell then it is stable and does not undergo reaction. Thus Neon does not need to react and can exist freely in nature.

Sodium with an electronic configuration of 2,8,1 has 1 electron in it's valence shell. As per octet rule, it is not stable and it must lose that 1 electron to become stable.

In order to lose that 1 electron sodium must react with other substances. Hence sodium cannot exist freely in nature.

5 0

3 years ago