Balance Ca + HCI +CaCl2 + H2

Answer: B. It must show that the mass of each element involved is conserved  by a chemical reaction.

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The correct statement why a chemical equation must be balanced is It must show that the mass of each element involved is conserved  by a chemical reaction.

Answer:

B. It must show that the mass of each element involved is conserved

by a chemical reaction.

Explanation:

a p e x, just took the quiz

Answer:

0.445 M

Explanation:

Molarity = moles/Volume

M = 9.95/22.35 = 0.445 M

Answer:

pH= 1.17

Explanation:

The neutralization reaction between HBr (acid) and KOH (base) is given by the following equation:

HBr(aq) + KOH(aq) → KBr(aq) + H₂O(l)

According to this equation, 1 mol of HBr reacts with 1 mol of KOH. Then, the moles can be expressed as the product between the molarity of the acid/base solution (M) and the volume in liters (V). So, we calculate the moles of acid and base:

Acid:

M(HBr) = 0.15 M = 0.15 mol/L

V(HBr) = 50.0 mL x 1 L/1000 mL = 0.05 L

moles of HBr = M(HBr) x V(HBr) = 0.15 mol/L x 0.05 L = 7.5 x 10⁻³ moles HBr

Base:

M(KOH) = 0.25 M = 0.25 mol/L

V(HBr) = 13.0 mL x 1 L/1000 mL = 0.013 L

moles of HBr = M(HBr) x V(HBr) = 0.25 mol/L x 0.013 L = 3.25 x 10⁻³ moles KOH

Now, we have: 7.5 x 10⁻³ moles HBr > 3.25 x 10⁻³ moles KOH

HBr is a strong acid and KOH is a strong base, so they are completely dissociated in water: the acid produces H⁺ ions and the base produces OH⁻ ions. So, the difference between the moles of HBr and the moles of KOH is equal to the moles of remaining H⁺ ions after neutralization:

moles of H⁺ = 7.5 x 10⁻³ moles HBr - 3.25 x 10⁻³ moles KOH = 4.25 x 10⁻³ moles H⁺

From the definition of pH:

pH = -log [H⁺]

The concentration of H⁺ ions is calculated from the moles of H⁺ divided into the total volume:

total volume = V(HBr) + V(KOH) = 0.05 L + 0.013 L = 0.063 L

[H⁺] = (moles of H⁺)/(total volume) = 4.25 x 10⁻³ moles/0.063 L = 0.067 M

Finally, we calculate the pH after neutralization:

pH = -log [H⁺] = -log (0.067) = 1.17

Answer:

They agree to ethical standards when they are licensed.

Explanation:

Answer:

C) They agree to ethical standards when they are licensed

Explanation:

Answer and Explanation:

The molar mass of a substance is all of the weights from the elements combined.

So, we have the elements

CU, S, and [tex]O_{4}[/tex]

CU has a mass is 65

S mass is 32

O has a mass of 16, but there's 4 atoms of O, so we do 16 times 4, which is 64.

Now we add.

65 + 32 + 64 is 161.

So, the answer is 160, or answer choice A.

#teamtrees #PAW (Plant And Water)

Answer:

Joan's hypothesis should make a prediction about the answer to the question. A hypothesis is just an educated guess on what you think the outcome will be on the experiment. The prediction must be testable and stated in if-then form. For example, a good hypothesis for Joan's experiment could be, I think that 1/2 cup of salt will make the water boil quicker, than water without salt.

Explanation:

Hope it helped!

Answer:

Explanation:

metamorphic

The equilibrium partial pressure of HF is 0.55 atm.

The equation of the reaction is;

        H2(g) + F2(g) ⇄ 2HF

I         2           1             0

C       -x           -x            +x

E     2 - x        1 - x           x

We know that;

pH2 = 2.0 atm

PF2 =  1.0 atm

pHF = ??

Kp = 0.45

So;

Kp = (pHF)^2/pH2. pF2

0.45 = x^2/(2 - x) (1 - x)

0.45 =  x^2/x^2 - 3x + 2

0.45(x^2 - 3x + 2) = x^2

0.45x^2 - 1.35x + 0.9 =  x^2

0.55 x^2 + 1.35x - 0.9 = 0

x = 0.55 atm

Learn more about equilibrium: https://brainly.com/question/3980297

Answer:

T₁ = P₁V₁T₂ / P₂V₂

Explanation:

The combine gas equation is given by:

P₁V₁ / T₁ = P₂V₂ / T₂

Where:

P₁ => is the initial pressure

V₁ => is the initial volume

T₁ => is the initial temperature

P₂ => is the final pressure

V₂ => is the final volume

T₂ => is the final temperature

Finally, we shall make T₁ the subject of the above expression. This can be obtained as follow:

P₁V₁ / T₁ = P₂V₂ / T₂

Cross multiply

T₁P₂V₂ = P₁V₁T₂

Divide both side by P₂V₂

T₁ = P₁V₁T₂ / P₂V₂

Thus, the formula for T₁ is:

T₁ = P₁V₁T₂ / P₂V₂

Answer:

[tex]Cs^+[/tex]

Explanation:

Cesium Lewis dot structure would look like this:

·Cs,  because it only has one valence electron. But, since it has a plus, that means we lost an electron. So, we have to get rid of the dot and you have:

[tex]Cs^+[/tex]

Answer:

a13+a13

Explanation:

The mass of ammonia prepared from 24.5 kg magnesium nitride, according to the reaction Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g), knowing that the process is 71% efficient is 5.87 kg.

The balanced reaction of production of ammonia is:

Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g)   (1)

First, let's find the number of moles of magnesium nitride

[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} [/tex]  (2)

Where:

[tex]m_{Mg_{3}N_{2}}[/tex]: is the mass of Mg₃N₂ = 24.5 kg

[tex]M_{Mg_{3}N_{2}}[/tex]: is the molar mass of Mg₃N₂ = 100.9494 g/mol

The number of moles is (eq 2):

[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} = \frac{24500 g}{100.9494 g/mol} = 242.70 \:moles [/tex]

We can calculate the mass of ammonia prepared, knowing that 1 mol of Mg₃N₂ reacts with 6 moles of H₂O to produce 3 moles of Mg(OH)₂ and 2 moles of NH₃ (reaction 1).

[tex]n_{NH_{3}} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*n_{Mg_{3}N_{2} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*242.70 \:moles \:Mg_{3}N_{2} = 485.4 \:moles[/tex]

Then, the mass of NH₃ is:

[tex] m_{NH_{3}} = n_{NH_{3}}*M_{NH_{3}} = 485.4 \:moles*17.031 g/mol = 8266.8 g = 8.27 kg [/tex]

Since the process is 71% efficient, the mass that can be prepared is:

[tex] m = 8.27 kg*0.71 = 5.87 kg [/tex]

Therefore, the mass of ammonia that can be prepared is 5.87 kg.

I hope it helps you!

Answer:

(1) Cl₂ is the limiting reactant.

(2) 8.18 g

Explanation:

First we convert the given masses of reactants into moles, using their respective molar masses:

0.070 moles of Cl₂ would react completely with (2 * 0.070) 0.14 moles of Na. There are more Na moles than that, so Na is the reactant in excess while Cl₂ is the limiting reactant.

Then we calculate how many moles of NaCl are formed, using the limiting reactant:

Finally we convert NaCl moles into grams:

Answer:

Zn + 2HCl → ZnCl₂ + H₂

Explanation:

First we write the equation using the molecular formulas instead of words:

We know zinc chloride is ZnCl₂ as the problem tells us the oxidation state of zinc in the products is +2, and chloride means Cl⁻¹.

Now we proceed to balance the reaction:

There are 2 Cl atoms and 2 H atoms on the right side, so we add a coefficient of 2 to HCl on the left side:

Answer:

2 C2H2 + 5 O2 = 4 CO2 + 2 H2O

I've checked this multiple times this should be it

Answer:

CH4

Explanation:

if it is wrong, i blame my brain

Answer:

the answer is gravitational potential energy

Answer:

Since the gravitational potential energy of an object is directly proportional to its height above the zero position, a doubling of the height will result in a doubling of the gravitational potential energy. A tripling of the height will result in a tripling of the gravitational potential energy.

Explanation:

Hope this helps?

Answer:

gimme that chocky milk.....

Explanation:

Answer:

m i l k

Explanation:

Answer:

It would be exactly 5.3586262014272155. But if you were to round it up it would be 5.35.

Answer:

3, 9, 3

Explanation:

The coefficient of 3 tells us that there are three molecules (the chemical unit of NH3). Each molecule of ammonia (NH3) is made up of 1 atom of nitrogen bonded to 3 atoms of hydrogen.

Since there are three molecules, we have three times the amount of atoms there are in one molecule.

3 x 1 = 3 nitrogen

3 x 3 = 9 hydrogen

Answer:B equals mass divided by volume

Explanation:I got hacks :)

Answer:

Which phrase describes air density? well b  

increases as altitude increases

equals mass divided by volume

pushes molecules in one direction

exerts less pressure as it increases

Explanation:

love you too!!!!!