The graph below shows the decay of a radioactive isotope. What is the half-life of the isotope?

]Which of the following describes the arrangement of particles in plasma?The particles are ionized and move independently of eac

Ugo [173]

The arrangement of the particles in a plasma would be that the particles are ionized and move independently of each other. Plasma is also called an ionized gas where it has free charged particles and are moving regardless of each other.

4 0

3 years ago

Read 2 more answers

How to draw Hess' Cycle for this question ?

NISA [10]

Answer : The standard enthalpy of formation of ethylene is, 51.8 kJ/mole

Explanation :

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.

According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

The formation reaction of $C_2H_4$ will be,

$2C(s)+2H_2(g)\rightarrow C_2H_4(g)$ $\Delta H_{formation}=?$

The intermediate balanced chemical reaction will be,

(1) $C_2H_4(g)+3O_2(g)\rightarrow 2CO_2(g)+2H_2O(l)$ $\Delta H_1=-1411kJ/mole$

(2) $C(s)+O_2(g)\rightarrow CO_2(g)$ $\Delta H_2=-393.7kJ/mole$

(3) $H_2(g)+\frac{1}{2}O_2(g)\rightarrow H_2O(l)$ $\Delta H_3=-285.9kJ/mole$

Now we will reverse the reaction 1, multiply reaction 2 and 3 by 2 then adding all the equations, we get :

(1) $2CO_2(g)+2H_2O(l)\rightarrow C_2H_4(g)+3O_2(g)$ $\Delta H_1=+1411kJ/mole$

(2) $2C(s)+2O_2(g)\rightarrow 2CO_2(g)$ $\Delta H_2=2\times (-393.7kJ/mole)=-787.4kJ/mole$

(3) $2H_2(g)+2O_2(g)\rightarrow 2H_2O(l)$ $\Delta H_3=2\times (-285.9kJ/mole)=-571.8kJ/mole$

The expression for enthalpy of formation of $C_2H_4$ will be,

$\Delta H_{formation}=\Delta H_1+\Delta H_2+\Delta H_3$

$\Delta H=(+1411kJ/mole)+(-787.4kJ/mole)+(-571.8kJ/mole)$

$\Delta H=51.8kJ/mole$

Therefore, the standard enthalpy of formation of ethylene is, 51.8 kJ/mole

7 0

2 years ago

i'm reasking this, i need help with this and it's due today. the answer isn't 30,240 minutes, it's the blanks i need filled in :

adelina 88 [10]

Answer:

Explanation:

24hours ×21 days=

you will get the answeer

3 0

3 years ago

A large piece of iron was reacted with an acid. What would happen to the rate of the reaction had the large piece been finely di

MAXImum [283]

Answer:

D: It will increase because smaller particles provide more surface area to react.

Explanation:

When the large iron is broken up into smaller pieces, there are more places for the iron to react (meaning there's more surface area). Think of it like taking the surface area of a big cube compared to the surface area of a bunch of small cubes. The sum of the surface areas of the small cubes will be greater than that of the large cube. As a result, more places for the iron to react will cause for a greater reaction.

4 0

3 years ago

If an atom with a mass of 47 amu has 22 neutrons, what atom is it?

LenaWriter [7]

Answer:

Manganese

Explanation:

At Mass - No neutrons = Atomic Number = #protons in nucleus

47 - 22 = 25 => At. No. 25 is Manganese (Mn)

7 0

2 years ago