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3 years ago

In what way would readings from a digital thermometer be preferable to those from a liquid-based thermometer?

2 answers:

5 0

I think its because its more accurate because it shows you the numbers rather than you reading the approximate temperature on a liquid thermometer

Lana71 [14]3 years ago

3 0

Readings from a digital thermometer can be more readily combined with computer software.

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Help me now, please!

Nikitich [7]

Answer:

1. SnO2 = 1; H2 = 2; Sn = 1; H2O = 2

2. I mole of SnO2 is required to react with 2 moles of H2 to produce 1 mole of Sn and 2 moles of H20.

The balanced equation represents 1 mole of SnO2

3. Total mass of reactants and products are each 154.71g respectively

Explanation:

1. According to the law of conservation of mass, the total mass of reactants in a chemical reaction is equal to the mass of products.

Therefore, a balanced chemical equation has equal number of moles of each atom on the reactants side and on the product side. The balanced chemical equation for the reaction above will be:

Sn02 + 2H2 + Energy -----> Sn + 2H2O

Sn has 1 mole of atoms on both sides

O has 2 moles of atoms on both sides

H has 4 miles of atoms on both sides.

2. According to the balanced chemical equation above,

1 mole of SnO2 reacts with 2 moles of H2 to produce 1 mole of An and 2 moles of H20.

This balanced equation represents 1 mole of SnO2.

3. The atomic masses of Sn, O and H are 118.71g, 16g and 1g respectively.

Therefore, the molar masses of the reactants and products are;

SnO2 = 118.71 + 16 * 2 = 150.72g

H2 = 2 *1 = 2g

H2O = 2 * 1 + 16 = 18g

Total mass of reactants = 150.71g + 2 * 2g = 154.72g

Total mass of products = 118.71 + 2 * 18g = 154.71g

3 0

3 years ago

If you want to produce 11 moles of NH3, how much H2 do you need?

leva [86]

Answer:

33 g of H2

Explanation:

N2 + 3 H2 -> 2 NH3

3 mol H2 -> 2 mol NH3

x -> 11 mol NH3

x= (11 mol NH3 * 3 mol H2)/ 2 mol NH3

x= 16.5 mol H2

1 mol H2 -> 2 g

16.5 mol H2 ->x

x= (16.5 mol H2 * 2 g)/ 1 mol H2

x= 33 g

3 0

3 years ago

Which of the following is the correct scientific notation for 0.0000782 g?

Dominik [7]

The correct scientific notation is 7.82 x 105 g

7 0

3 years ago

Read 2 more answers

The forensic technician at a crime scene has just prepared a luminol stock solution by adding 15.0 gg of luminol into a total vo

Firdavs [7]

Answer:

1.13 M

Explanation:

Given data

Mass of luminol (solute): 15.0 g

Volume of solution = volume of water = 75.0 mL = 0.0750 L

Molar mass of luminol: 177.16 g/mol

The molarity of the stock solution of luminol is:

M = mass of solute / molar mass of solute × liters of solution

M = 15.0 g / 177.16 g/mol × 0.0750 L

M = 1.13 M

6 0

3 years ago

A sample of hexane (C6H14) has a mass of 0.580 g. The sample is burned in a bomb calorimeter that has a mass of 1.900 kg and a s

Talja [164]

Answer: The enthalpy of the reaction is -4134.3 kJ/mol

Explanation:

To calculate the heat absorbed by the calorimeter, we use the equation:

$q=mc\Delta T$

where,

q = heat absorbed

m = mass of calorimeter = 1.900 kg = 1900 g (Conversion factor: 1 kg = 1000 g)

c = heat capacity of calorimeter = 3.21 J/g.K

$\Delta T$ = change in temperature = 4.542 K

Putting values in above equation, we get:

$q=1900g\times 3.21J/g.K\times 4.542K=27701.66J=27.7kJ$

Heat released by the calorimeter will be equal to the heat absorbed by the reaction.

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of hexane = 0.580 g

Molar mass of hexane = 86.18 g/mol

Putting values in above equation, we get:

$\text{Moles of hexane}=\frac{0.580g}{86.18g/mol}=0.0067mol$

To calculate the enthalpy change of the reaction, we use the equation:

$\Delta H_{rxn}=\frac{q}{n}$

where,

q = amount of heat released = -27.7 kJ

n = number of moles of hexane= 0.0067 moles

$\Delta H_{rxn}$ = enthalpy change of the reaction

Putting values in above equation, we get:

$\Delta H_{rxn}=\frac{-27.7kJ}{0.0067mol}=-4134.3kJ/mol$

Hence, the enthalpy of the reaction is -4134.3 kJ/mol

5 0

3 years ago