a pure substance could be either an element or a compound true or false?

Answer:

The ability of an atom to attract electrons.

Explanation:

Electronegativity is the ability of an atom to attract electrons.  In a bonded pair, electrons tend to stay closer to the more electronegative atom.  Atoms become more electronegative near the top right of the Periodic Table, with the highest electronegativity being Fluorine.

Answer:

See explanation

Explanation:

Now , we have the equation of the reaction as;

2H2S(g) + 302(g)------->2SO2(g) + 2H2O(g)

This equation shows that SO2 gas is produced in the process. Let us recall that this same SO2 gas is the anhydride of H2SO4. This means that it can dissolve in water to form H2SO4

So, when SO2 dissolve in rain droplets, then H2SO4 is formed thereby lowering the pH of rain water. This is acid rain.

Answer:

1+2 = 12

Explanation:

this is a math equation, not a chemical formula

Answer: 2 moles

Explanation:

AM of Al 27

Answer:

261.3368

Explanation:

The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Ba(NO3)2, or 261.3368 grams.

Na more reactive than Cu

Given

Copper in a solution of NaCl

Required

The displacement theory

Solution

A single replacement reaction is a chemical reaction in which one element replaces the other elements of a compound to produce new elements and compounds

Not all of these reactions can occur. We can use the activity series, which is a list of elements that can replace other elements below / to the right of them in a single replacement reaction.

The voltaic series:  

Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe²⁺-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Fe³⁺-Ag-Pt-Au  

The electrode which is easier to reduce than the hydrogen (H2) electrode has a positive sign (E red= +) and is located to the right of the voltaic series (right of H)  

The electrode which is easier to oxidize than the hydrogen (H2) electrode and is difficult to experience reduction has a negative sign (E red= -) and is located to the left of the voltaic series (left of H)

Reaction

Cu + NaCl≠

The existing copper element can not replace the sodium element, which is on the left side so the reaction will not occur.

But if it is reversed, then a reaction can occur

2 Na + CuCl2 → Cu + 2 NaCl

Answer:

Fission and fusion are two physical processes that produce massive amounts of energy from atoms. They yield millions of times more energy than other sources through nuclear reactions.

Explanation:

Hope this answer your question.

Given :

Number of He atoms, [tex]n = 3.4\times 10^{24}[/tex] atoms.

To Find :

How many grams are their in given number of He atoms.

Solution :

We know, molecular mass of He is 4 g. It means that their are [tex]6.022 \times 10^{23}[/tex] atoms in 4 g of He.

Let, number of gram He in [tex]3.4\times 10^{24}[/tex] atoms is x , so :

[tex]x = \dfrac{3.4\times 10^{24}}{6.022\times 10^{23}}\times 4\\\\x = $$22.58\ g[/tex]

Therefore, grams of He atoms is 22.58 g .

Answer:

1. c 2. b that's what i think i learned this in middle school i dont completely remember

Answer:

Ok so, I would say D) because decreasing the blood glucose is actually recycling the organic chemicals. Your body uses everything in your body, filtering out the unusable chemicals and such.

Explanation:

Science :3

Answer:

going without without masks is like to play with a dirty things which is very undesired and unwanted .corona virus is very serious world wide epidemic which is surrounded in all region due to our carelessness many lives are taken due to our carelessness. so please wear mask and maintain social distance to fight against all types of communicable diseases. I hope please be rational and aware.

Answer:

Hola porfa ayudame si podes

Answer:

36

Explanation:

There are 6 Carbon atoms, 12 Hydrogen atoms, and 18 Oxygen atoms.

Answer:

it is synthesis reaction

Answer:

See Explanation

Explanation:

The question is incomplete; as the mixtures are not given.

However, I'll give a general explanation on how to go about it and I'll also give an example.

The percentage of a component in a mixture is calculated as:

[tex]\%C_E = \frac{E}{T} * 100\%[/tex]

Where

E = Amount of element/component

T = Amount of all elements/components

Take for instance:

In [tex](Ca(OH)_2)[/tex]

The amount of all elements is: (i.e formula mass of [tex](Ca(OH)_2)[/tex])

[tex]T = 1 * Ca + 2 * H + 2 * O[/tex]

[tex]T = 1 * 40 + 2 * 1 + 2 * 16[/tex]

[tex]T = 74[/tex]

The amount of calcium is: (i.e formula mass of calcium)

[tex]E = 1 * Ca[/tex]

[tex]E = 1 * 40[/tex]

[tex]E = 40[/tex]

So, the percentage component of calcium is:

[tex]\%C_E = \frac{E}{T} * 100\%[/tex]

[tex]\%C_E = \frac{40}{74} * 100\%[/tex]

[tex]\%C_E = \frac{4000}{74}\%[/tex]

[tex]\%C_E = 54.05\%[/tex]

The amount of hydrogen is:

[tex]E = 2 * H[/tex]

[tex]E = 2 * 1[/tex]

[tex]E = 2[/tex]

So, the percentage component of hydrogen is:

[tex]\%C_E = \frac{E}{T} * 100\%[/tex]

[tex]\%C_E = \frac{2}{74} * 100\%[/tex]

[tex]\%C_E = \frac{200}{74}\%[/tex]

[tex]\%C_E = 2.70\%[/tex]

Similarly, for oxygen:

The amount of oxygen is:

[tex]E = 2 * O[/tex]

[tex]E = 2 * 16[/tex]

[tex]E = 32[/tex]

So, the percentage component of oxygen is:

[tex]\%C_E = \frac{E}{T} * 100\%[/tex]

[tex]\%C_E = \frac{32}{74} * 100\%[/tex]

[tex]\%C_E = \frac{3200}{74}\%[/tex]

[tex]\%C_E = 43.24\%[/tex]

Answer:

D. The flesh should return to normal after you press it.

Explanation:

The water content stored in the flesh of the fish, paired with the elasticity are both indicators of freshness, and will cause the flesh to return to normal after its been pressed.

Answer:

D) A positive but not linear relationship

Explanation:

This comes from the equation Ek=1/2mv^2

Where Ek is Kinetic Energy, m is mass, and v is the speed (or velocity).

As we can see in the equation, the relation is not linear but quadratic and it is positive.

Answer:

D) A positive but not linear relationship

Explanation:

Speed is equal to distance divided by time. ... Therefore, the kinetic energy of an object is proportional to the square of its velocity (speed). In other words, If there is a twofold increase in speed, the kinetic energy will increase by a factor of four.

Answer:

Mitochondria is known as the powerhouse of the cell as it provides teh energy required for the cell to carry out cellular respiration and cellular process that maintain the cell

Answer:

26.34 moles

Explanation:

Answer:

Your ability to move and lift objects refers to muscular strength. It's measured by how much force you can exert for a short period of time and how much weight you can lift.

Explanation:

Explanation:

The reaction is given as;

SO2(g) ⇄ S(s) + O2(g) ΔH° = 297 kJ

This reaction is an endothermic reaction because of the positive value of the  ΔH°. Increasing the temperature for an equilibrium reaction with froward reaction being endothermic leads to increase in equilibrium constant (K).

Regarding equilibrium concentration;

In an equilibrium reaction, any change to the system is annuled. If there is an increase in temperature, in order to annul that, the forward reaction is favoured leading to increase in concentration of of the products and decrease in reactants.

The new volume : V₂ = 1185.9 cm³

Given

V₁ = 571 cm³

T₁ = 260 K

T₂ = 540 K

Required

The new volume (V₂)

Solution

Charles's Law  

When the gas pressure is kept constant, the gas volume is proportional to the temperature  

[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]

Input the value :

V₂ = V₁.T₂/T₁

V₂ = 571 x 540 / 260

V₂ = 1185.9 cm³

Answer:

V₁ = 571 cm³

T₁ = 260 K

T₂ = 540 K your right

Explanation:

The new volume will by 1185.9

Answer:

the awnser is reactants

Answer:

the metal is gold I'd say

The mass of one metal atom is [tex]1.770\times 10^{-22}[/tex]grams.

The metal atom is palladium.

Explanation:

Given:

A face-centered unit cell.

The density of the unit cell is [tex]12020 kg/m^3[/tex].

The edge length of the unit cell 389.08 pm

To find:

The mass of one atom of the metal

Solution:

The density of the unit cell = d = [tex]12020 kg/m^3[/tex]

The edge length of the unit cell = a = 389.08 pm

[tex]1 pm = 10^{-12} m\\a=389.08 pm=389.08\times 10^{-12} m=3.8908\times 10^{-10}m[/tex]

Total number of atoms in F.C.C unit cell = z = 4

The atomic mass of the metal atom = M

The density of the unit cell is given by:

[tex]d=\frac{z\times M}{N_A\times a^3}\\12020 kg/m^3=\frac{4\times M}{6.022\times 10^{23}mol^{-1}\times (3.8908\times 10^{-10}m)^3}\\M=0.106586 kg/mol\\1 kg=1000 g\\M=0.106586 kg/mol=0.106586 \times 1000 g/mol\\M=106.586 g/mol[/tex]

The mass of one mole of metal atom = 106.586 g

The mass of 1 atom of metal :

[tex]=\frac{106.586 g}{6.022\times 10^{23}}\\=1.770\times 10^{-22} g[/tex]

The mass of one metal atom is [tex]1.770\times 10^{-22}[/tex] grams.

The atomic mass of the metal atom is 106.586 g/mol which is close to the atomic mass of the palladium. Hence, the metal atom is palladium.

Learn more about the density of unit cell here:

brainly.com/question/7210717?referrer=searchResults

brainly.com/question/1594030?referrer=searchResults

Answer:

A reflected ray always comes off the surface of a material at an angle equal to the angle at which the incoming ray hit the surface. In physics, you'll hear this called the law of reflection. You've probably heard this law stated as "the angle of incidence equals the angle of reflection

Explanation:

Answer: Equilibrium

Explanation:

The reactions which do not go on completion and in which the reactant forms product and the products goes back to the reactants simultaneously are known as equilibrium reactions.

For a chemical equilibrium reaction, equilibrium state is achieved when the rate of forward reaction becomes equals to rate of the backward reaction which means the products are being made as quickly as reactants

Equilibrium state is the state when reactants and products are present but the concentrations does not change with time.

Answer:

monke

Explanation:

because my mum told me we are all monke

Answer:

Hydrogen is the most explosive element