1/2 - 3/7=??????????????????????

A gas occupies a volume of 50.0 mL at 100K and 630 mmHg. At what temperature would

rodikova [14]

PV / T = P'V' / T'

V = V'

P / T = P' / T'

P = 630 mmHg
T = 100 K
P' = 1760 mmHg
T' = ?

630 / 100 = 1760 / T'

T' = 1760 / 6,3

T' = 279,36 K

T' ≈ 280 K

3 0

3 years ago

Classify the following as either Sexual or Asexual Reproduction. Explain your choice.

Furkat [3]

A) Asexual
b) Sexual
c) Sexual
d) Asexual

3 0

3 years ago

A student dissolves 15.0 g of ammonium chloride(NH4Cl) in 250. 0 g of water in a well-insulated open cup. She then observes the

iren2701 [21]

Answer:

1) Endothermic.

2) $Q_{rxn}=4435.04J$

3) $\Delta _rH=15.8kJ/mol$

Explanation:

Hello there!

1) In this case, for these calorimetry problems, we can realize that since the temperature decreases the reaction is endothermic because it is absorbing heat from the solution, that is why the temperature goes from 22.00 °C to 16.0°C.

2) Now, for the total heat released by the reaction, we first need to assume that all of it is released by the solution since it is possible to assume that the calorimeter is perfectly isolated. In such a way, it is also valid to assume that the specific heat of the solution is 4.184 J/(g°C) as it is mostly water, therefore, the heat released by the reaction is:

$Q_{rxn}=-(15.0g+250.0g)*4.184\frac{J}{g\°C}(16.0-20.0)\°C\\\\ Q_{rxn}=4435.04J$

3) Finally, since the enthalpy of reaction is calculated by dividing the heat released by the reaction over the moles of the solute, in this case NH4Cl, we proceed as follows:

$\Delta _rH=\frac{ Q_{rxn}}{n}\\\\\Delta _rH= \frac{ 4435.04J}{15.0g*\frac{1mol}{53.49g} } *\frac{1kJ}{1000J} \\\\\Delta _rH=15.8kJ/mol$

Best regards!

4 0

3 years ago

How does the greenhouse effect relate to the theme of stability and change

Nadya [2.5K]

The greenhouse effect increases the temperature of the Earth by trapping heat in our atmosphere. This keeps the temperature of the Earth higher than it would be if direct heating by the Sun was the only source of warming.
When the sunlight reaches the surface of the Earth, some of it is absorbed which warms the ground and some bounces back to space as heat. Greenhouse gases that are in the atmosphere absorb and then redirect some of this heat back towards the Earth.

8 0

3 years ago

Be sure to answer all parts. Propane (C3H8) is a minor component of natural gas and is used in domestic cooking and heating. (a)

Leokris [45]

Answer:

For a: The balanced chemical equation is given below.

For b: The mass of carbon dioxide produced will be $1.07\times 10^3g$

Explanation:

For a:

Every balanced chemical equation follows law of conservation of mass.

This law states that mass can neither be created nor can be destroyed but it can only be transformed from one form to another form.

This law also states that the total number of individual atoms on the reactant side must be equal to the total number of individual atoms on the product side.

For the given reaction, the balance chemical equation follows:

$C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g)$