1a.calculate the relative formula mass of magnesium oxide when the relative atomic masses are O=16 Mg=24
1b.calculate the percentage by mass of magnesium in magnesium oxide​

Answer:

5

Explanation:

Carbon tetrachloride has molecular formula as  CCl4 , so from this it is evident that there are 4 atoms of Chlorine & 1 atom of carbon is present, in total 5 molecules are present in carbon tetra

Answer:

its 5

Explanation:

Answer:

Option A:

Zn(s) + Cu^(2+) (aq) → Cu(s) + Zn^(2+)(aq)

Explanation:

The half reactions given are:

Zn(s) → Zn^(2+)(aq) + 2e^(-)

Cu^(2+) (aq) + 2e^(-) → Cu(s)

From the given half reactions, we can see that in the first one, Zn undergoes oxidation to produce Zn^(2+).

While in the second half reaction, Cu^(2+) is reduced to Cu.

Thus, for the overall reaction, we will add both half reactions to get;

Zn(s) + Cu^(2+) (aq) + 2e^(-) → Cu(s) + Zn^(2+)(aq) + 2e^(-)

2e^(-) will cancel out to give us;

Zn(s) + Cu^(2+) (aq) → Cu(s) + Zn^(2+)(aq)

Explanation:

Los tejidos que conforman el tejido fundamental son los siguientes:

-Parénquima

-Colénquima

-Esclerénquima.

El tejido fundamental constituye la parte principal del cuerpo de la planta porque intervienen en funciones tan importantes para el desarrollo  y sostenimiento de la planta como el proceso de  la fotosíntesis, el almacenamiento de agua y  de  nutrientes .

Answer: This satisfies the law of definite proportion or constant proportion and it can be proven below.

Explanation:

The law of constant or definite proportion states that all pure samples of the same compound no matter how they are made; are made up of the same elements combined in the same proportion by mass. The can be verified by finding the ratio of copper to oxygen in the both experiment listed above.

In the first experiment:

1.37 g of cupric oxide contains 1.098 g copper therefore oxygen = 1.37 − 1.098

=0.272 g

The ratio of copper to oxygen is=

1.098 ÷ 0.272

= 4:1

In the SECOND or next experiment:

1.476 g of cupric oxide contains 1.17 g copper Therefore oxygen = 1.476−1.17

=0.306g

The ratio of copper to oxygen is =

=1.176 ÷ 0.306

=3.8:1

Which is approximately≃4:1.

In conclusion, despite the different methods of the experiments, composition of copper of copper in the two different samples are the same and the cupric oxide obtained from different sources contain the same elements ( copper and oxygen) combined in the SAME ratio.

Answer:

A

Explanation:

Electrons are significantly smaller than neutrons and protons.

Electrons have a diameter of less than 10^-16 centimeters, whereas protons and neutrons have a radius of about 10^-13 centimeters.

Answer:

Therefore mole ratio is [tex]H_{2}O[/tex] : [tex]KAl(SO_{4} )_{2}[/tex] is 12 :1  

Empirical formula is [tex]KAl(SO_{4} )_{2}. 12 H_{2}O[/tex].

Explanation:

The chemical formula of a hydrate  

Moles of anhydrous [tex]KAl(SO_{4} )_{2}[/tex]  

Molar mass of [tex]KAl(SO_{4} )_{2}[/tex] = 258.21 g /mol  

Mass of anhydrous [tex]KAl(SO_{4} )_{2}[/tex] = [mass of aluminum cup + alum after 2nd heating] –[ mass of empty cup]  

                                                   = 3.5 g – 2.4 g  

                                                   = 1.1 g

Moles of [tex]KAl(SO_{4} )_{2}[/tex]= mass / molar mass  

                                    = 1.1 g / 258.21 g per mol  

                                   = 0.00426 mol [tex]KAl(SO_{4} )_{2}[/tex]

The mole ratio of the H2O to [tex]KAl(SO_{4} )_{2}[/tex]

Mole ratio = moles of H2O/ moles of [tex]KAl(SO_{4} )_{2}[/tex]

                  = 0.05 mol H2O / 0.00462 mol [tex]KAl(SO_{4} )_{2}[/tex]

                 = 11.7

We can round the 11.7 to closest whole number = 12

Therefore mole ratio is [tex]H_{2}O[/tex] : [tex]KAl(SO_{4} )_{2}[/tex] is 12 :1  

Empirical formula = [tex]KAl(SO_{4} )_{2}. 12 H_{2}O[/tex]  

So we have 12 moles of water as the water of hydration in the empirical formula.  

Alum hydrate is that the white crystalline solid after heating it'll start melting due to the water of hydration present in it then again solid will remain within the aluminum cup once all the water is given off within the sort of vapors.  

b) if the scholar used 2.20 g of the sample but within the calculation, he started with 2.0 g sample then  

when the mass of water is calculated using this data the mass of water is going to be higher therefore it gives more moles of water within the hydrate.  

So the final answer is going to be artificially high.

Answer:

Explanation:

2,5M

Answer:

2,5m

Explanation:

c=n:v

Answer:

1.67g H2CO3 are produced

Explanation:

Based on the reaction:

2NaHCO3 → Na2CO3 + H2CO3

2 moles of NaHCO3 produce 1 mole of Na2CO3 and 1 mole of H2CO3

To solve this question we need to find the moles of Na2CO3 = Moles of H2CO3. With their moles we can find the mass of H2CO3 as follows:

Moles Na2CO3 -Molar mass: 105.99g/mol-

2.86g Na2CO3 * (1mol/105.99g) = 0.02698 moles Na2CO3 = Moles H2CO3

Mass H2CO3 -Molar mass: 62.03g/mol-

0.02698 moles  * (62.03g/mol) =

Answer:

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aiejand iefjwe

eekkfwefwe f

opw fwfwfew

efefwefwefwi

Explanation:

The missing options are;

A) in

B) to

C) of

D) about

Answer:

B: To

Explanation:

In the question, for the gap to be filled, we need to find a preposition that will show the direction of the reason for canceling.

The most appropriate one will be "to" because it is the one that most qualifies the reason for canceling as a result of bad weather.

Answer:

1s2 2s2 2p6 3s2 3p6

Explanation:

Chlorine is a groups 17 element. The halogens for ions by accepting one electron to form univalent negative ions.

Since chlorine normally contains seventeen electrons, the chloride ion consists of eighteen electrons.

Hence the electronic configuration of chlorine ion is; 1s2 2s2 2p6 3s2 3p6.

Answer:

Ba

Explanation:

Answer:

lemon juice............

Answer:

1 Ca(OH)2 + 2 HCl ---> 1 CaCl2 + 2 H2O

Answer:

A balanced chemical equation must always include coefficients on every reactant and product.

Explanation:

A balanced chemical equation does not need to include coefficients on every reactant and product.

For example, below is a balanced chemical equation in which the reactants and the products have no coefficients whatsoever:

NaOH(aq) + HCl (aq) -----> NaCl (s) + H2O (l)

Of course, a properly written chemical equation must include the states of matter of all the substances in the reaction and the number of atoms of each element must balance both in the reactant and product sides of the equation. Generally, a balanced chemical equation must obey the law of conservation of matter which opines that matter can neither be created nor destroyed but can only be converted from one form to another.

Hence, that a balanced chemical equation must always include coefficients on every reactant and product is not true.

i) Las bacterias son organismos microscópicos unicelulares que prosperan en diversos entornos. Estos organismos pueden vivir en el suelo, el océano y dentro del intestino humano.

ii) Un virus es un agente infeccioso submicroscópico que se replica solo dentro de las células vivas de un organismo. Los virus infectan todas las formas de vida, desde animales y plantas hasta microorganismos, incluidas bacterias y arqueas.

Answer: D is the answer since it is the product of this equation

Explanation: HOPE I AM RIGHT AND IT HELPS!!!

need more explanation feel free to comment in the comment box

Answer:

The answer is HSO4- is a weak acid which will be C

The acid dissociation constant, ka, of HSO4- indicates that it is a strong acid. Details about acid dissociation constant can be found below.

The acid dissociation constant denoted by Ka is the measure of the strength of an acid.

The dissociation constant of an acid is used to identify strong acids from their weak counterparts. Strong acids have high Ka values while weak acids have low Ka values.

According to this question, the Ka of HSO4- is 1.2 × 10-², which is quite high.

Therefore, the dissociation constant, ka, of HSO4- suggests that it is a strong acid.

Learn more about acid dissociation constant at: https://brainly.com/question/4363472

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Answer:

Mg

Explanation:

Mg forms 2+ ions and mgcl2 has a melting point over 700°C I believe.

Answer:

Lines of longitude

Explanation:

Lines of direction and lines of longitude are horizontally and vertically lines, respectively.

The phrases vertical and horizontal are frequently used to define directions: a vertical line runs up and down, whereas a horizontal line crosses.

Answer:

1.31

Explanation:

Given,

Given mass of Zn = 15 g

Volume of solution = 175 ml

Mass of Zn = 65.4

No. of moles of solute

= Given mass of Zn / mass of Zn

= 15 / 65.4

= 0.22 ( approximately )

Formula : -

Molarity

= No. of moles of solute / Volume of solution (L)

= 0.22 / ( 175 / 1000 )

= 0.22 / 0.175

= 1.257

= 1.31 ( approximately )

Explanation:

When chlorine bonds and becomes stable, (had a full outer electron shell), because we know that chlorine has 7 electrons in it’s outer shell, it requires 1 to gain noble gas structure. So, when if bonds with an element and then becomes stable, the gaining of an electron means it becomes a negatively charged ion. (an ion being a charged particle.)

Answer:

volume in Liter = 2.50 L

Explanation:

Given:

Na2CO3 = 0.2 M

Molar mass of Na2CO3 = 106 g/mol

Mass of Na2CO3 solution = 53 gram

Find:

Volume of Na2CO3

Computation:

Number of mol of Na2CO3  = (53 g) / (1.06 x 10² g/mol)

Number of mol of Na2CO3  = 0.5 mol

M = Number of mol / volume in Liter

0.2 = 0.5/ volume in Liter

volume in Liter = 0.5 / 0.2

volume in Liter = 2.50 L

Answer:

0.20 mol

Explanation:

Let's consider the reduction of iron from an aqueous solution of iron (II).

Fe²⁺ + 2 e⁻ ⇒ Fe

The molar mass of Fe is 55.85 g/mol. The moles corresponding to 5.6 g of Fe are:

5.6 g × 1 mol/55.85 g = 0.10 mol

2 moles of electrons are required to deposit 1 mole of Fe. The moles of electrons required to deposit 0.10 moles of Fe are

0.10 mol Fe × 2 mol e⁻/1 mol Fe = 0.20 mol e⁻

0.20 mol of electrons is required to deposit 5.6g of iron from a solution of iron (2) tetraoxosulphate(6)

 The reduction of iron from an aqueous solution of iron (II).

[tex]Fe^{+2} +2e^{-} \rightarrow Fe[/tex]

The formula for number of moles is as follows:-

[tex]Number \ of \ moles=\frac{Mass}{Molar\ mass}[/tex]

The molar mass of Fe is 55.85 g/mol. The moles corresponding to 5.6 g of Fe are:

[tex]5.6 g \times\frac{1\ mol}{55.85\ g} = 0.10 \ mol[/tex]

2 moles of electrons are required to deposit 1 mole of Fe. The moles of electrons required to deposit 0.10 moles of Fe are:-

[tex]0.10 mol Fe\times\frac{2\ mol\ e^{-} }{1\ mol\ e^{-}} = 0.20 \ mol e^{-}[/tex]

Hence, 0.20 mol of electrons is required to deposit 5.6g of iron.

To know more about:-

brainly.com/question/12513822

Answer:

Mg is oxidized and Pb is the oxidizing agent

Explanation:

Answer:

ii and iv

Explanation:

atomic mass is the sum of protons and neutrons

protons ( postively charged) usually have the same number like electrons( negatively charged)

Answer:

i dont know why a, i here

Explanation: