What happens if someone let's go of the button on an electric door bell

The transition from the gas phase directly to the solid phase is called:

solmaris [256]

The answer is depostion

8 0

4 years ago

Randy is building a house. He wants to put stucco on the outside walls of his house. To make stucco, he needs sand. He lives on

allochka39001 [22]

Answer:

(c)-He separates the larger pebbles and other debris from the finer sand by sifting it with wire mesh.

Explanation:

A mixture is an association of substances that not react between them. It can be homogeneous when it's not possible to see the substances, or heterogeneous when it's possible to see each the substances.

Randy separates the substances of the soil with a wire mesh, so it's possible to define the substances, then the mixture is heterogeneous.

8 0

4 years ago

The aromatic hydrocarbon cymene (C10H14) is found in nearly 100 spices and fragrances, including coriander, anise, and thyme. Th

andrezito [222]

Answer : The thermal energy produced during the complete combustion of one mole of cymene is -7193 kJ/mole

Explanation :

First we have to calculate the heat released by the combustion.

$q=c\times \Delta T$

where,

q = heat released = ?

$c$ = specific heat of calorimeter = $3.640kJ/^oC$

$\Delta T$ = change in temperature = $19.35^oC$

Now put all the given values in the above formula, we get:

$q=3.640kJ/^oC\times (19.35)^oC$

$q=70.43kJ$

Thus, the heat released by the combustion = 70.43 kJ

Now we have to calculate the molar enthalpy combustion.

$\Delta H=-\frac{q}{n}$

where,

$\Delta H$ = molar enthalpy combustion = ?

q = heat released = 70.43 kJ

n = number of moles cymene = $\frac{\text{Mass of cymene}}{\text{Molar mass of cymene}}=\frac{1.608g}{164.22g/mol}=0.009792mole$

$\Delta H=-\frac{70.43kJ}{0.009792mole}=-7193kJ/mole$

Therefore, the thermal energy produced during the complete combustion of one mole of cymene is -7193 kJ/mole

4 0

3 years ago

Convert the following names to balanced formulas.

yulyashka [42]

You can reduce the charges and subscripts so it is PbS2

8 0

3 years ago

Two reactions and their equilibrium constants are given. A + 2 B − ⇀ ↽ − 2 C K 1 = 2.79 2 C − ⇀ ↽ − D K 2 = 0.186 Calculate the

vfiekz [6]

Answer:

K=1.93

Explanation:

Given reactions are:

A +2B ⇄ 2C K1=2.79

2C ⇄ D K2=0.186

D⇄ A+ 2B K=?

If we reverse the reaction then the euillibrium constant also become reciprocal of original value:

3rd reaction is a combination of reciprocal of 1st and 2nd reaction

2C⇄A +2B 1/K1;........................1

D ⇄ 2C 1/K2; ..............................2

On adding 1 and 2

D ⇄A +2B $K=\frac{1}{K1} \times\frac{1}{K2};$

$K=\frac{1}{2.79} \times\frac{1}{0.186};$

K=1.93

4 0

4 years ago