Reaction rate describes the blank
of a chemical reaction

Answer:

Percent yield =  57%

Explanation:

Given data:

Mass of nitrogen = 15.0 g

Mass of hydrogen = 15.0 g

Mass of ammonia produced = 10.5 g

Percent yield = ?

Solution:

Chemical equation:

N₂+ 3H₂      →   2NH₃

Number of moles of hydrogen:

Number of moles = mass/molar mass

Number of moles = 15.0 g/ 2 g/mol

Number of moles = 7.5 mol

Number of moles of nitrogen:

Number of moles = mass/molar mass

Number of moles = 15.0 g/ 28 g/mol

Number of moles = 0.54 mol

Now we will compare the moles of ammonia with nitrogen and hydrogen from balance chemical equation.

              N₂       :        NH₃

               1         :          2

           0.54       :     2×0.54 = 1.08

             H₂         :           NH₃

              3           :            2

              7.5        :      2/3×7.5= 5 mol

Theoretical yield of ammonia:

Mass = number of moles × molar mass

Mass = 1.08 × 17 g/mol

Mass = 18.36 g

Percent yield:

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

Percent yield = (10.5 g/ 18.36 g) ×100

Percent yield = 0.57 ×100

Percent yield =  57%

Explanation:

Unordered items;  

          cell, elephant, human body, school bus, organ ,molecule.

This problem deals with the organization of life. We move from cells, to tissues, organs, and then systems.

       Molecule

        Cell

        Organ

        Human body

        Elephant

        School bus

School bus is the largest from the giving items although it is non-living.

Answer:

1 is B, 2 is B a cold front

Explanation:

In order for a front to form, two air masses have to collide, and for 2 a cold front is represented by a red ljine with half circles

The answer to this is true.

Answer:2:saturated

3:it got darker

4:it halved/unsaturated

Explanation:

Answer:

Answer:2:saturated

3:it got darker

4:it halved/unsaturated

Explanation:

Answer:

1. earth metal 2. halogen 3.The elements are arranged in seven horizontal rows, called periods or series, and 18 vertical columns, called groups. ... Elements in the periodic table are organized according to their properties.

Inventor: Dmitri Mendeleev please name most brainliest

Answer:

The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or "L shell"), then the "3 shell" (or "M shell"), and so on farther and farther from the nucleus.

Nice written.

Is it written by you yourself or you have copied it from somewhere?

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{1.204 \times {10}^{24} }{6.02 \times {10}^{23} } \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

I think the particle size

Explanation:

By decreasing the particle size of a reactant, we are increasing its surface area. The greater the surface area, the higher the chance of collisions, thus the faster the rate of reaction.

increasing the particle size will decrease the rate of reaction.

conclusion:

The smaller the particle size the faster the reaction.

The statement which is not correct is that: the rate of a reaction increases with increasing particle size.

Discussion;

The addition of catalyst, increase in temperature and reactant concentration all are factors which increase the rate of a chemical reaction.

Decreasing the particle size of reactants also increases the rate of reaction. This is because upon decreasing particle size, the surface area of the reactants is increased and the reaction is able to take place at a faster rate.

Read more on rate of reaction;

https://brainly.com/question/24795637

Explanation:

The compound disilicon tetraoxide has the formula;

        Si₂O₄;

 This compound is held together by a polar covalent bond. A polar covalent bond occurs between two species that shares electrons. In this bond type, the more electronegative element draws the shared electrons more closer to itself.

Answer:

Metamorphic

Explanation:

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question we have

[tex]density = \frac{9 \times {10}^{5} }{3 \times {10}^{ - 1} } \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

the one with less thermal energy

Explanation:

thermal energy is heat

Answer:

GOTTTEM

Explanation:

Answer:

If we have more protons in the nucleus, then they hold it tighter

Answer:

true

Explanation:

took test

Cl2 + 2RbI → 2RbCl + I2  is possible while I2 + NiBr2 → NiI2 + Br2 is not possible.

It will do us a lot of good to write out the equations again;

Cl2 + 2RbI → 2RbCl + I2       Yes

I2 + NiBr2 → NiI2 + Br2         No

If we look at the reaction closely, they are displacement reactions. It is worthy to note that a specie can only displace another specie which lies below it in the activity series. The activity series is an arrangement of elements in order of decreasing reactivity.

The activity series of the halogens is; fluorine > chlorine > bromine > iodine.

Since chlorine is above iodine in the activity series, Cl2 + 2RbI → 2RbCl + I2 is possible.

Iodine is less than bromine in the activity series hence the reaction  I2 + NiBr2 → NiI2 + Br2 is not possible.

Learn more: https://brainly.com/question/14365792

Answer:

Cl2 + 2RbI --> 2RbCl + I2 = yes

I2 + NiBr2 --> NiI2 + Br2 = no

Explanation:

I just took the assinment

Answer:

it is false it cannot be a model

Answer:

28g

Explanation:

Given parameters:

Number of moles of hydrogen  = 3moles

Unknown:

Mass of nitrogen used = ?

Solution:

 To solve this problem, let us establish the balanced reaction equation first;

             N₂  + 3H₂ →  2NH₃

From the balanced reaction equation;

                 3 mole of H₂ will combine with 1 mole of N₂

Now,

   Mass of Nitrogen  = number of moles x molar mass

         Molar mass of N₂  = 2(14) = 28g/mol

   Mass of Nitrogen  = 1 mole x 28g/mole  = 28g

Answer: 1.91 moles

Explanation:

First you want to find the molar mass of NaCL

Na = 22.99g  Cl = 35.45g

22.99g + 35.45g = 54.44g

Then divide 111.5g by 54.44g and this will give you moles.

Answer:

C. the two atoms must be of the same element

Answer:

I think it would have a LOW frequency rate.

Explanation:

ΔH for this reaction : -2668.4 (exothermic)

The change in enthalpy in the formation of 1 mole of the elements is called enthalpy of formation  

The enthalpy of formation measured in standard conditions (25 ° C, 1 atm) is called the standard enthalpy of formation (ΔHf °)  

(ΔH) can be positive (endothermic = requires heat) or negative (exothermic = releasing heat)  

The value of ° H ° can be calculated from the change in enthalpy of standard formation:  

∆H ° rxn = ∑n ∆Hf ° (product) - ∑n ∆Hf ° (reactants)  

you can search the value of ΔHf on the internet

∆H ° rxn =( ∆H Al₂O₃+∆H AlCl₃+3.∆H NO + 6.∆H H₂O)-(∆H Al+∆H NH₄ClO₄)

[tex]\tt \Delta H^o~rxn=(-1669.8+-704+(3\times 90.4)+(6.\times -241.8)-(3\times 0+3\times -295)\\\\\Delta H6o~rxn=-3553.4+885=-2668.4~kJ/mol[/tex]

Answer:

a new substance was forming

Explanation:

Answer:

Gosha Gosha

Explanation:

‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎‏‏‎ ‎

Explanation:

When magnesium reacts with chlorine then it forms magnesium chloride.

Equation -

Mg + Cl₂ → MgCl₂

This is the example of Combination reaction.

Answer:

the Ray's go right through it

Explanation:

the Ray's are so small they punch right through them

Answer:

Explanation:

The reason why is based in something called the plasma frequency of the metal of a mirror. A metal, as you may know, is composed of a series of atom (ion, effectively) cores - nuclei, together with some, but not all, of their bound electrons - which contribute the remaining outermost electrons of their unbound forms to a communally shared "electron sea" - kind of like a giant, distributed omnidirectional covalent bond that extends all throughout the whole metal crystal (here we're just considering a single crystal for simplicity). The electrons are quantumed out all over the full extent of the crystal and effectively form a sort of "gas" throughout and permeating the metal.

When an electromagnetic wave approaches that gas, the free charges within it - the electrons - start oscillating, and as they do so, they set up another wave going outward at the same time as the first is going in. This begins as soon as the first wave begins to impinge.

However, if the wave oscillation is fast enough, the electrons can't keep up due to their mass, and thus they are unable to form the reflected wave. The frequency at which this occurs is called the metal's plasma frequency (and is inversely proportional to the square root of the mass, so that a high mass particle would have a lower plasma frequency). The name comes from the fact that the metal can be thought of in a sense as a kind of "solid plasma" - ions with free electrons, the difference with what most people think of as a "plasma" being here the ions are not free to move about of their own accord.

Answer:

When manganese(IV) oxide is added to hydrogen peroxide, bubbles of oxygen are given off. To make oxygen in the laboratory, hydrogen peroxide is poured into a conical flask containing some manganese(IV) oxide. The gas produced is collected in an upside-down gas jar filled with water.