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2 years ago

What are characteristics of absorption spectra? Check all that apply.

Chemistry

1 answer:

Amanda [17]2 years ago

7 0

The absorption spectrum is the result of absorption of light radiation by a material (solid or liquid) as a function of wavelength or frequency. The figure is shown below:

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Calculate the theoretical value for the number of moles of CO2 that should have been produced in each balloon assuming that 1.45

musickatia [10]

Answer:

For 1 antacid tablet (in ballon1) we get .0173 moles of CO2

for 2 tablets (in balloon 2) we get: 2*0,0173= 0.0346 moles of CO2

For 3 tablets (in balloon 3) we get 3* 0.0173 = 0.0519 moles of CO2

Explanation:

The complete question:

Calculate the theoretical value for the number of moles of CO2 that should have been produced in each balloon assuming that 1.45 g of NaHCO3 is present in an antacid tablet. Use stoichiometry (a mole ratio conversion must be present) to find your answers (there should be three: one answer for each balloon).

Balloon 1 had 1 antacid tab

Baloon 2 had 2

Balloon 3 had 3

Step 1: Data given

1.45 g of NaHCO3 is present in an antacid tablet

Molar mass of NaHCO3 = 84.00 g/mol

Step 2: The balanced equation

NaHCO3 + H2O → NaOH + H2O + CO2

Step 3: Calculate moles of NaHCO3

Moles NaHCO3 = mass NaHCO3 / molar mass NaHCO3

1.45g / 84.0 g/mol = .0173 moles

Step 4: Calculate moles CO2

For 1 mol NaHCO3 we need 1 mol H2O to produce 1 mol NaOH 1 mol H2O and 1 mol CO2

For 0.0173 moles NaHCO3 we'll get 0.0173 moles CO2

so for 1 antacid tablet we get .0173 moles of CO2

for 2 tablets we get: 2*0,0173 = 0.0346 moles of CO2

For 3 tablets we get 3* 0.0173 = 0.0519 moles of CO2

5 0

2 years ago

Use bond energies to calculate the enthalpy change for the following reaction. H2(g) + CO2(g) ⟶ H2O(g) + CO(g)

Maslowich

Answer: The enthalpy change for this reaction is 392 Joules

Explanation:

The balanced chemical reaction is,

$H_2(g)+CO_2(g)\rightarrow H_2O(g)+CO(g)$

The expression for enthalpy change is,

$\Delta H=\sum [n\times B.E_{reactant}]-\sum [n\times B.E_{product}]$

$\Delta H=[(n_{H_2}\times B.E_{H_2})+(n_{CO_2}\times B.E_{CO_2})]-[(n_{H_2O}\times B.E_{H_2O})+(n_{CO}\times B.E_{CO})]$

where,

n = number of moles

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

$\Delta H=[(1\times 1\times H-H)+(1\times 2\times C=O) ]-[(1\times 2\times O-H)+(2\times 1\times C-O)]$

$\Delta H=[(1\times 1\times 436)+(1\times 2\times 799) ]-[(1\times 2\times 463)+(2\times 1\times 358)]$

$\Delta H=392J$

Therefore, the enthalpy change for this reaction is 392 Joules

3 0

1 year ago

What is the mass of nickel(ii) nitrate (182.71 g/mol) dissolved in 25.0 ml of 0.100 m ni(no3)2 solution?

Studentka2010 [4]

The mass of ni(NO3)2 that dissolved in 25.0 ml of 0.100m ni(NO3)2 solution is calculated as follows

fin the number of moles = molarity x volume in liters

=25 x0.100/ 1000= 2.5 x10^-3 moles
mass = mass x molar mass
= 2.5 x10^-3 moles x 182.71 g/mol = 0.457 grams

4 0

2 years ago

Read 2 more answers

Identify the number of moles in 369 grams of calcium hydroxide. Use the periodic table and the polyatomic ion resource.

topjm [15]

Answer : The number of moles in 369 grams of calcium hydroxide is, 4.98 moles

Explanation : Given,

Mass of calcium hydroxide = 369 g

Molar mass of calcium hydroxide = 74.093 g/mole

Formula used :

$\text{Moles of calcium hydroxide}=\frac{\text{Mass of calcium hydroxide}}{\text{Molar mass of calcium hydroxide}}$

Now put all the given values in this formula, we get the moles of calcium hydroxide.

$\text{Moles of calcium hydroxide}=\frac{369g}{74.093g/mole}=4.98mole$

Therefore, the number of moles in 369 grams of calcium hydroxide is, 4.98 moles

7 0

2 years ago

Calculate the number of oxygen atoms in 2.00 moles of Mn2O7

cluponka [151]

First you should know that there is seven oxygen atoms in one Mn2O7
So
2.00 moles of Mn2O7 contain 14.00 moles of oxygen...
Then you multiply this no. with Avagadro no....
from formula
Number of moles= no. of particles/avagadro's no..
14.00×6.02×10²³=84.28 atoms of oxygen...

7 0

2 years ago