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3 years ago

Low grades ore are less desirable than a high grade ores because?

1 answer:

8 0

This is because a higher grade will result in a higher GPA which can help people get into college and even help them get scholarships. Lower grades will prevent you from getting into a good college and from getting scholarships. Higher grades an also result in free things! Car insurance rates go lower for kids with better grades/ a higher GPA.

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Given these reactions, where X represents a generic metal or metalloid 1 ) H 2 ( g ) + 1 2 O 2 ( g ) ⟶ H 2 O ( g ) Δ H 1 = − 241

anygoal [31]

Answer : The enthalpy of the given reaction will be, -1048.6 kJ

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.

The main reaction is:

$XCl_4(s)+2H_2O(l)\rightarrow XO_2(s)+4HCl(g)$ $\Delta H=?$

The intermediate balanced chemical reactions are:

(1) $H_2(g)+\frac{1}{2}O_2(g)\rightarrow H_2O(g)$ $\Delta H_1=-241.8kJ$

(2) $X(s)+2Cl_2(g)\rightarrow XCl_4(s)$ $\Delta H_2=+461.9kJ$

(3) $\frac{1}{2}H_2(g)+\frac{1}{2}Cl_2(g)\rightarrow HCl(g)$ $\Delta H_3=-92.3kJ$

(4) $X(s)+O_2(g)\rightarrow XO_2(s)$ $\Delta H_4=-789.1kJ$

(5) $H_2O(g)\rightarrow H_2O(l)$ $\Delta H_5=-44.0kJ$

Now reversing reaction 2, multiplying reaction 3 by 4, reversing reaction 1 and multiplying by 2, reversing reaction 5 and multiplying by 2 and then adding all the equations, we get :

(1) $2H_2O(g)\rightarrow 2H_2(g)+O_2(g)$ $\Delta H_1=2\times 241.8kJ=483.6kJ$

(2) $XCl_4(s)\rightarrow X(s)+2Cl_2(g)$ $\Delta H_2=-461.9kJ$

(3) $2H_2(g)+2Cl_2(g)\rightarrow 4HCl(g)$ $\Delta H_3=4\times -92.3kJ=-369.2kJ$

(4) $X(s)+O_2(g)\rightarrow XO_2(s)$ $\Delta H_4=-789.1kJ$

(5) $2H_2O(l)\rightarrow 2H_2O(g)$ $\Delta H_5=2\times 44.0kJ=88.0kJ$

The expression for enthalpy of main reaction will be:

$\Delta H=\Delta H_1+\Delta H_2+\Delta H_3+\Delta H_4+\Delta H_5$

$\Delta H=(483.6)+(-461.9)+(-369.2)+(-789.1)+(88.0)$

$\Delta H=-1048.6kJ$

Therefore, the enthalpy of the given reaction will be, -1048.6 kJ

4 0

3 years ago

1. How does a star's life begin?

Phantasy [73]

Answer:

A star begins its life as a cloud of dust and gas (mainly hydrogen) known as a nebula. A protostar is formed when gravity causes the dust and gas of a nebula to clump together in a process called accretion. ... If a critical temperature in the core of a protostar is reached, then nuclear fusion begins and a star is born.

Explanation:

4 0

3 years ago

Read 2 more answers

What is Density?:

Kryger [21]

Answer:

Density is defined as how tightly or loosely packed a substance is, or to the number of things or people in a certain area.

3 0

3 years ago

4. Balance the following chemical equation. Say what the coefficients "a"

lisabon 2012 [21]

Answer:

a = 4

b = 3

Explanation:

SOLUTION :-

Balance it by using 'hit & trial' method , and you'll get the answer :-

2Fe₂O + 3C → 4Fe + 3CO₂

⇒ a = 4 ; b = 3

VERIFICATION :-

In reactant side of equation :-

Number of atoms in Fe = 2×2 = 4
Number of atoms in O = 2×3 = 6
Number of atoms in C = 3×1 = 3

In product side of equation :-

Number of atoms in Fe = 4×1 = 4
Number of atoms in C = 3×1 = 3
Number of atoms in O = 3×2 = 6

Number of atoms of each element is equal in both reactant & product side of equation. Hence , the equation is balanced.

6 0

3 years ago

If you have a negative ion, what happened to the outer shell of the atom?

Nastasia [14]

It will lose them and become stable

8 0

3 years ago