Using prior knowledge to forecast what will happen next

A. How many moles of ammonium sulfate will be produced with 25.56 grams of ammonia gas

Irina-Kira [14]

I do not know do you?

3 0

3 years ago

Which is correct if 15,390,000 is rounded to two significant figures?

BARSIC [14]

Answer:

Explanation:

Remark

This is one of those questions that you need the choices. You can't tell what you should enter. For example, in scientific notation, you would get 1.5*10^7.

Or you could keep it as an integer and round to two places 150,000,000,

I would pick scientific notation if you know how to use it. Otherwise use the interger format.

7 0

2 years ago

Sodium carbonate can be made by heating sodium bicarbonate: 2NaHCO3(s) → Na2CO3(s) + CO2(g) + H2O(g) At 25°C, for this reaction,

insens350 [35]

Answer:

401.17 K is the minimum temperature at which the reaction will become spontaneous under standard state conditions.

Explanation:

The expression for the standard change in free energy is:

$\Delta G=\Delta H-T\times \Delta S$

Where,

$\Delta G$ is the change in the Gibbs free energy.

T is the absolute temperature. (T in kelvins)

$\Delta H$ is the enthalpy change of the reaction.

$\Delta S$ is the change in entropy.

Given at:-

Temperature = 25.0 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T₁ = (25.0 + 273.15) K = 298.15 K

$\Delta H$ = 128.9 kJ/mol

$\Delta G$ = 33.1 kJ/mol

Applying in the above equation, we get as:-

$33.1=128.9-298.15\times \Delta S$

$-29815\Delta S=-9580$

$\Delta S=-9580$ = 0.32131 kJ/Kmol

So, For reaction to be spontaneous, $\Delta G$

Thus, For minimum temperature:-

$\Delta H-T\times \Delta S=0$

$128.9-T\times 0.32131=0$

$T=\frac{128.9}{0.32131}=401.17\ K$

Hence, 401.17 K is the minimum temperature at which the reaction will become spontaneous under standard state conditions.

6 0

3 years ago

Recycled r134a refrigerant cannot exceed what levels of contaminants

Contact [7]

Answer is:
1) lubricant - 500 ppm by weight.
2) moisture - 50 ppm by weight.
3) non-condensable gases (air) - 150 ppm by weight.
Standard J2099 specific the maximum levels of contaminants for R134a.
ppm (parts-per-million, 10⁻⁶) is value that represents the part of a whole number in units of 1/1000000.

7 0

3 years ago

Design a concept map that shows the relationships among the following terms: volume , derived unit , mass , base unit , time , a

Svetlanka [38]

Base unit is the fundamental unit of measurement that is not mutually dependent. The seven base units are,

Length - meter

Mass- kilogram

Time - second

Temperature - Kelvin

Current - Ampere

Luminous intensity - Candela

Amount of matter - mole

Derived units are derived from the seven base units. Like the area (square meters) is the square of length (meters), volume is the cube of length.

5 0

3 years ago