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2 years ago

Which temperate change indicate an increase in the average kinetic energy of the molecules in a sample?

Chemistry

1 answer:

Mkey [24]2 years ago

8 0

An increase in temperature increases the average kinetic energy of molecules.

When the temperature of a molecule increases, the molecule starts to move at a faster rate. The faster a molecule moves, the more kinetic energy it has.

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Baking soda (NaHCO3) can be added to a fruit mix solution to create a carbonated drink. An example is the reaction between bakin

DanielleElmas [232]

Answer:

74.4 ml

Explanation:

C₆H₈O₇(aq) + 3NaHCO₃(s) => Na₃C₆H₅O₃(aq + 3CO₂(g) + 3H₂O(l)

Given 15g = 15g/84g/mol = 0.1786mole Sodium Bicarbonate

From equation stoichiometry 3moles NaHCO₃ is needed for each mole citric acid or, moles of citric acid needed is 1/3 of moles sodium bicarbonate used.

Therefore, for complete reaction of 0.1786 mole NaHCO₃ one would need 1/3 of 0.1786 mole citric acid or 0.0595 mole H-citrate.

The question is now what volume of 0.8M H-citrate solution would contain 0.0595mole of the H-citrate? This can be determined from the equation defining molarity. That is => Molarity = moles solute / Liters of solution

=> Volume (Liters) = moles citric acid / Molarity of citric acid solution

=> Volume needed in liters = 0.0.0595 mole/0.80M = 0.0744 Liters or 74.4 ml

6 0

2 years ago

Which of the following is an example of a chemical reaction?

nevsk [136]

Answer:

where is the option I can't see plz give the option first the I try to give answer

3 0

2 years ago

Identify the total number of molecules in the chemical formula: 6CH4 a 6 b 10 c 24 d 30

Anon25 [30]

Answer: A.6

Explanation:

8 0

1 year ago

Ethanol melts at -114 degree C. The enthalpy of fusion

Brut [27]

Answer: The heat required is 6.88 kJ.

Explanation:

The conversions involved in this process are :

$(1):ethanol(s)(-135^0C)\rightarrow ethanol(s)(-114^0C)\\\\(2):ethanol(s)(-114^0C)\rightarrow ethanol(l)(-114^0C)\\\\(3):ethanol(l)(-114^0C)\rightarrow ethanol(l)(-50^0C)$

Now we have to calculate the enthalpy change.

$\Delta H=[m\times c_{p,s}\times (T_{final}-T_{initial})]+n\times \Delta H_{fusion}+[m\times c_{p,l}\times (T_{final}-T_{initial})]+n\times \Delta H_{vap}+[m\times c_{p,g}\times (T_{final}-T_{initial})]$

where,

$\Delta H$ = enthalpy change = ?

m = mass of ethanol = 25.0 g

$c_{p,s}$ = specific heat of solid ethanol= 0.97 J/gK

$c_{p,l}$ = specific heat of liquid ethanol = 2.31 J/gK

n = number of moles of ethanol = $\frac{\text{Mass of ethanol}}{\text{Molar mass of ethanol}}=\frac{25.0g}{46g/mole}=0.543mole$

$\Delta H_{fusion}$ = enthalpy change for fusion = 5.02 KJ/mole = 5020 J/mole

$T_{final}-T_{initial}=\Delta T$ = change in temperature

The value of change in temperature always same in Kelvin and degree Celsius.

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

$\Delta H=[25.0 g\times 0.97J/gK\times (-114-(-135)K]+0.534mole\times 5020J/mole+[25.0g\times 2.31J/gK\times (-50-(-114))K]$

$\Delta H=6885.93J=6.88kJ$ (1 KJ = 1000 J)

Therefore, the heat required is 6.88 kJ

3 0

2 years ago

How many significant figures are in the number 0.00346

Oliga [24]

Answer:

Explanation:

Significant figures are the number of digits in a value, often a measurement, that to the degree of accuracy of the value. All non-zero numbers ARE significant. ...

Zeros between two non-zero digits ARE significant. ...

Leading zeros are NOT significant. ...

Trailing zeros to the right of the decimal are significant. ...

Trailing zeros in a whole number with the decimal shown ARE significant.contributes

8 0

2 years ago