Please help I have no idea tbh

The molar mass of I2 is 253.80 g/mol, and the molar mass of NI3 is 394.71 g/mol. How many moles of I2 will form 3.58 g of NI3?

Nat2105 [25]

To answer the problem above first we need to find the difference of molar mass of NI3 from I2, 394.71 g/mol - 253.80 g/mol = 140.91 g/mol. Knowing the molar mass of the difference of NI3 from I2, in equation mass (g) / moles (mol) = molar mass, then we substitute. 3.58g / moles = 140.91 g/mol.
moles = 3.58 / 140.91 = 0.025 moles.

6 0

4 years ago

The ideal gas heat capacity of nitrogen varies with temperature. It is given by:

hammer [34]

Answer:

A) 1059 J/mol

B) 17,920 J/mol

Explanation:

Given that:

Cp = 29.42 - (2.170*10^-3 ) T + (0.0582*10^-5 ) T2 + (1.305*10^-8 ) T3 – (0.823*10^-11) T4

R (constant) = 8.314

We know that:

$C_p=C_v+R$

We can determine $C_v$ from above if we make $C_v$ the subject of the formula as:

$C_v$ $=C_p-R$

$C_V = 29.42-(2.7*10^{-3})T+(5.82*10^{-7})T2-(1.305*10^{-8})T3-(8.23*10^{-12})T4-8.314$

$C_V = 21.106-(2.7*10^{-3})T+(5.82*10^{-7})T2-(1.305*10^{-8})T3-(8.23*10^{-12})T4$

A).

The formula for calculating change in internal energy is given as:

$dU=C_vdT$

If we integrate above data into the equation; it implies that:

$U2-U1=\int\limits^{500}_{450}(21.106-(2.7*10^{-3})T+(5.82*10^{-7})T2-(1.305*10^{-8})T3-(8.23*10^{-12})T4\,) du$

$U2-U1=\int\limits^{500}_{450}(21.106-(2.7*10^{-3})T/1+(5.82*10^{-7})T2/2-(1.305*10^{-8})T3/3-(8.23*10^{-12})T4/4\,)$

$U2-U1= 1059J/mol$

Hence, the internal energy that must be added to nitrogen in order to increase its temperature from 450 to 500 K = 1059 J/mol.

B).

If we repeat part A for an initial temperature of 273 K and final temperature of 1073 K.

then T = 273 K & T2 = 1073 K

∴

$U2-U1=\int\limits^{500}_{450}(21.106-(2.7*10^{-3})T/1+(5.82*10^{-7})T2/2-(1.305*10^{-8})T3/3-(8.23*10^{-12})T4/4\,)$

$U2-U1=\int\limits^{500}_{450}(21.106-(2.7*10^{-3})273/1+(5.82*10^{-7})1073/2-(1.305*10^{-8})T3/3-(8.23*10^{-12})T4/4\,)$

$U2-U1= 17,920 J/mol$

3 0

4 years ago

HELPPP ME WITH SICENCE PLZZZZZZ

Goryan [66]

Answer:

molecules

Explanation:

molecules because the summer like atoms and Sciences sciency to be honest

7 0

3 years ago

Read 2 more answers

• Draw lewis dot structures for an atom of each of following elements:

marin [14]

Answer:

Explanation:

Lewis dot structures represent the symbol of an atom we're looking at and the number of valence electrons it has. This number is represented by the sum of dots around the symbol.

Potassium is in group 1A, this means it only has one valence electron, so we draw K with one dot in its Lewis diagram;
Argon is in group 8A, this means it has eight valence electrons, so we draw Ar with 8 dots around it in its Lewis diagram;
Silicon is in group 4A, this means it has four valence electrons, so we draw Si with 4 dots around it in its Lewis diagram;
Arsenic is in group 5A, this means it has five valence electrons, so we draw As with 5 dots around it in its Lewis diagram.

Those are represented in the image attached below:

5 0

3 years ago

3. A PS6 plugged into a 120 V outlet uses 3 Amps. What is the Resistance rating of

blondinia [14]

Answer:

R = 40 ohms

Explanation:

Given that,

The voltage of outlet, V = 120 V

Current flowing through the device, I = 3 A

We need to find the Resistance rating of the power cord. Let the resistance is R. We know that,

Ohm's law, V = IR

Put all the values,

$R=\dfrac{V}{I}\\\\R=\dfrac{120}{3}\\\\R=40\ \Omega$

So, the resistance rating of the power cord is equal to 40 ohms.

8 0

3 years ago