what coefficient will go in the box​

Answer:

1. 0.25 moldm¯³.

2. 9.125 gdm¯³.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

2HCl + Na2CO3 → 2NaCl + H2O + CO2

From the balanced equation,

The mole ratio of the acid, HCl (nA) = 2

The mole ratio of the base, Na2CO3 (nB) = 1

1. Determination of the concentration of the acid, HCl in moldm¯³.

Volume of acid, HCl (Va) = 20 cm³

Volume of base, Na2CO3 (Va) = 25 cm³

Concentration of base, Na2CO3 (Cb) = 0.1 moldm¯³

The mole ratio of the acid, HCl (nA) = 2

The mole ratio of the base, Na2CO3 (nB) = 1

Concentration of acid, HCl (Ca) =?

Cava /CbVb = nA/nB

Ca × 20 / 0.1 × 25 = 2/1

Ca × 20 / 2.5 = 2

Cross multiply

Ca × 20 = 2.5 × 2

Ca × 20 = 5

Divide both side by 20

Ca = 5/20

Ca = 0.25 moldm¯³

Thus, the concentration of the acid, HCl in moldm¯³ is 0.25 moldm¯³

2. Determination of the concentration of the acid, HCl in gdm¯³

Concentration of the acid, HCl = 0.25 moldm¯³

Molar mass of HCl = 1 + 35.5 = 36.5 g/mol

Concentration of the acid, HCl in gdm¯³ =?

Conc. in moldm¯³ = Conc. in gdm¯³ /Molar mass

0.25 = Conc. in gdm¯³ /36.5

Cross multiply

Conc. in gdm¯³ = 0.25 × 36.5

Conc. in gdm¯³ = 9.125 gdm¯³.

Answer:

2AL(ClO3)3 → 2ALCl3 + 9O2

Explanation:

Answer:

Based on the periodic law

Explanation:

All the elements on the periodic table were constructed based on the periodic law.

Henry Moseley in the 1900s re-stated the periodic law by changing the basis of the law from atomic weight to atomic number. The present periodic law is therefore "the properties of elements are a periodic function of their atomic number".

Answer:the 4th one is incorrect,and the 1st one is incorrect hope this helps.

Adsorption is defined as a process in which gas molecules tend to adsorb on the surface of a solid solvent.

Therefore, the statement solids are not able to act as a solvent if a gas is the solute, is false.

On the other hand, gases can also act as a solvent if a solid is the solute.

Explanation:

Adsorption is defined as a process in which gas molecules tend to adsorb on the surface of a solid solvent.

Therefore, the statement solids are not able to act as a solvent if a gas is the solute, is false.

On the other hand, gases can also act as a solvent if a solid is the solute.For example, air present in the surrounding acts as a solvent and solid substances present in the surrounding acts as a solute.

Hence, the statement gases are not able to act as a solvent if a solid is the solute, is false.

Thus, we can conclude that following are the statements which are incorrect.

Solids are not able to act as a solvent if a gas is the solute.

Gases are not able to act as a solvent if a solid is the solute.

Answer:

a: iron is a substance

Explanation:

because its hard and brittle and classified as a metal

Answer:

190+2=192

Explanation:

192 add it 192 added

Answer: they are right

Explanation:

Answer:

The dependent variable is the number of clams developing from fertilized eggs.

The independent variable is the water temperature

The optimum temperature for clam development is 30 degrees centigrade.

Explanation:

The graph of the number of clams developing from fertilized eggs and water temperature is attached to this answer.

The independent variable is being manipulated in an experiment. As it changes, it produces a corresponding change in the dependent variable.

Here, the water temperature is the independent variable. As it changes, the number of clams developing from fertilized eggs (dependent variable) also changes alongside.

The optimum temperature is the temperature at which the greatest number of clams developing from fertilized eggs is produced. We can see from the graph that this temperature is 30 degrees centigrade.

Answer:

λ  = 0.5×10⁻⁶ m

Explanation:

Given data:

Frequency of light = 6.01 ×10¹⁴ Hz

Wavelength of light = ?

Solution:

Formula:

Speed of light = wavelength × frequency

Speed of light = 3×10⁸ m/s

3×10⁸ m/s = λ × 6.01 ×10¹⁴ Hz

λ  = 3×10⁸ m/s / 6.01 ×10¹⁴ Hz

        Hz = 1/s

λ  = 0.5×10⁻⁶ m

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{13 \times {10}^{24} }{6.02 \times {10}^{23} } \\ = 21.594684...[/tex]

We have the final answer as

Hope this helps you

Answer:

1250kg

Explanation:

Given parameters:

Acceleration  = 1.2m/s²

Force  = 1500N

Unknown:

Mass on the vehicle  = ?

Solution:

According to newton's second law of motion:

  Force  = mass x acceleration

Since mass is the unknown, insert the parameters and solve;

       1500  = mass x 1.2

        mass = [tex]\frac{1500}{1.2}[/tex]   = 1250kg

Answer:

E is the anwser

Answer:

The answer is (c)

Explanation:

Answer:

C. The most common religion is Catholism.

Explanation:

I'm taking the quiz rn.

Hope this might help a little

The chemical equation is said to be balanced if the number of atoms in the reactants and products is the same

Equation balanced ⇒ total number of atoms in reactants(on the left)= total number of atoms in products(on the right)

H₂+O₂---> H₂O

Reactants : H₂, O₂

Products : H₂O

not balanced

H₂O₂ ---> H₂O+O₂

Reactants : H₂O₂

Products : H₂O, O₂

not balanced

Na+O₂ ---> Na₂O

Reactants : Na, O₂

Products :  Na₂O

not balanced

N₂+H₂ ---> NH₃

Reactants : N₂, H₂

Products :  NH₃

not balanced

P₄+O₂---> P₄O₁₀

Reactants : P₄, O₂

Products :  P₄O₁₀

not balanced

Fe+H₂O ----> Fe₃O₄ + H₂

Reactants : Fe, H₂O

Products :  Fe₃O₄

not balanced

Answer:

Aluminium (A1) -Used in the production of duralumin alloy for use in the construction of aeroplane bodies. 3. Silicon (Si) -To make microchips 4. Sulphur (S) -To make matches, fireworks and for the manufacture of sulphuric acid 5.

Explanation:

Hope this helped!

Answer:

yes

Explanation:

we use different elements and compounds in our life ex salt and iron but most of the substances found in our environment are mixture btw scientists need to classified substances to work with our substances and to study pure substances hope it helps u

Answer:

D. Volume

Explanation:

Properties mentioned in the question;

colour = gray

Nonmetallic

Density = 3.8 g/mL

Volume = 48.3 mL

Of the mentioned, which is extensive ?

Extensive properties are those properties that are proportional to the amount of substance present.

The correct option is D. Volume. The other properties do not change with increasing or decreasing amount of the mineral

Answer:

istopes is a situation in which each of two or more forms of same element that contain equal number of proton....while ions of an atoms are with extra electrons or missing electrons so they tends to differ

Answer:

[tex].5865 \\ \\ \\ \\ \\ \5865[/tex]

[tex] \\ \\ 5865 \inf \inft \cos( \\ \) [/tex]

Answer:

carbon

Explanation:

carbon has 6e- hence belong to group 4 and period 2

Answer:

Boron

Explanation:

Both silicon and boron are metalloids, and boron belongs on the second row (period)

Answer:

ions

Explanation:

Individual atoms of the same element but having slightly different number of protons and electrons are called ions.

Ion is a charged particle.

When the number of protons > electrons the body is positively charged.

When the number of electrons > protons the body is negatively charged.

Charged particles are called ions.

Answer:

Carbohydrates can be represented by the stoichiometric formula (CH2O)n, where n is the number of carbons in the molecule. Therefore, the ratio of carbon to hydrogen to oxygen is 1:2:1 in carbohydrate molecules.

Explanation:

May I have brainliest please? :)

Answer:

(CH2O)n, where n is the number of carbons in the molecule.

Explanation:

Also remember the 1:2:1 ratio of carbon:hydrogen:oxygen

Answer:

Theoretical yield = 16.76 g

Percent yield = 87%

Explanation:

Given data:

Mass of iron oxide = 23.5 g

Theoretical yield of iron = ?

Actual yield of iron = 14.5 g

Percent yield of iron = ?

Solution:

Chemical equation:

2Fe₂O₃ + 3C     →  4Fe + 3CO₂

Number of moles of iron oxide:

Number of moles = mass/molar mass

Number of moles = 23.5 g/ 159.69 g/mol

Number of moles = 0.15 mol

Now we will compare the mole of iron oxide with iron metal.

                      Fe₂O₃         :            Fe

                         2              :              4

                      0.15            :          4/2×0.15 = 0.3

Mass of iron:

Mass = number of moles × molar mass

Mass = 0.3 mol × 55.85 g/mol

Mass = 16.76 g

Percent yield:

percent yield = (actual yield / theoretical yield)× 100

Percent yield = (14.5 g / 16.76 g) × 100

Percent yield = 0.87 × 100

Percent yield = 87%

Answer:

I tried the answer above and it’s correct

Explanation:

Loose sugar dissolves much faster than a sugar cube because loose sugar (a) has greater surface area.

When any solute dissolve in ground into small pieces it dissolve faster in solvent than large pieces because in small ones the large surface area is exposed into solvent.

With the greater surface area is exposer, the contact in between the solute particles and the solvent is more. this is the reason that loose sugar cube dissolve much faster than sugar cube as sugar cube has less surface area in contact with solvent.

Thus, Loose sugar dissolves much faster than a sugar cube because loose sugar (a) has greater surface area.

To learn more about solubility here

https://brainly.com/question/8685116

#SPJ1

Explanation:

- sodium is an alikal metal and chlorine is a halogen

-sodium forms metallic bond while chlorine cant

- chlorine is an oxidant while sodium is a reducing agent

Answer:

There are four σ bonds and no lone pairs around phosphorous atom in the lewis structure of H3PO4 molecule. Therefore total number of VSPER pairs are four. Therefore, shape of molecule around phosphorous atom is tetrahedral.

Explanation:

There are four σ bonds and no lone pairs around phosphorous atom in the lewis structure of H3PO4 molecule. Therefore total number of VSPER pairs are four. Therefore, shape of molecule around phosphorous atom is tetrahedral.

therefore total number of vsper pairs of four. Therefore, shape of molecule around phosphorous atom is tetrahedral.