I need help with these

Answer:

Hydrogen

Explanation:

Answer:

Ron and Hermoine

Explanation:

They always fought over petty things, but at the end, they did end up together!

(Answer for your question about love and friendship being a central theme in Harry Potter and the Philosopher's stone)

*ALSO, MY ANSWER MIGHT BE WRONG* so be sure to use a pencil just in case!

Answer:

hope this helps.answer is in the picture

Answer:

Dekameter

Explanation:

Answer:

the oxidation number of those elements is 2 because some of them are molecules

Answer:

400 cm³ of ammonia, NH₃.

Explanation:

The balanced equation for the reaction is given below:

N₂ + 3H₂ —> 2NH₃

From the balanced equation above,

3 cm³ of H₂ reacted to produce 2 cm³ of NH₃.

Finally, we shall determine the maximum volume of ammonia, NH₃ produced from the reaction. This can be obtained as illustrated below:

From the balanced equation above,

3 cm³ of H₂ reacted to produce 2 cm³ of NH₃.

Therefore, 600 cm³ of H₂ will react to produce = (600 × 2)/3 = 400 cm³ of NH₃.

Thus, 400 cm³ of ammonia, NH₃ were obtained from the reaction.

Answer: The empirical formula of one that contains 30.45% nitrogen is [tex]NO_{2}[/tex].

Explanation:

Given: Mass of nitrogen = 30.45 g

Let us assume that the mass of given oxide is 100 grams.

As the atomic mass of nitrogen is 14.0067 g. So, moles of nitrogen will be calculated as follows.

[tex]Moles = \frac{mass}{molarmass}\\= \frac{30.45 g}{14.0067 g/mol}\\= 2.17 mol[/tex]

Also, mass of oxygen = (100 - 30.45) g = 69.55 g

Atomic mass of oxygen is 15.9994 g/mol. So, moles of oxygen will be as follows.

[tex]Moles = \frac{mass}{molarmass}\\= \frac{69.55 g}{15.9994 g/mol}\\= 4.34 mol[/tex]

The ratio of both the atoms is as follows.

[tex]\frac{4.34}{2.17} = 2[/tex]

This means that gas has 2 moles of oxygen to 1 mole of nitrogen. Hence, the formula of oxide is [tex]NO_{2}[/tex].

Thus, we can conclude that the empirical formula of one that contains 30.45% nitrogen is [tex]NO_{2}[/tex].

Answer:

when it comes to adding or subtracting numbers, his final answer should have the same number of decimal places as the least precise value.

For example if you add 2 numbers; 10.443 + 3.5 , 10.443 has 3 decimal places and 3.5 has only one decimal place.

Therefore 3.5 is the less precise value.

So when adding these 2 values the final answer should have only one decimal place.

after adding we get 13.943 but it can have upto one decimal place. then the second decimal place is less than 5 so the answer should be rounded off to 13.9.

the answer is the same number of decimal places as the least precise value

Explanation:

I think this is the answer I'm not sure

Answer: the same number of decimal places as the least precise value

Explanation:

Answer:

64g of [tex]\bold{CH_{3}OH}\dashrightarrow[/tex]44.8L

vapour density of [tex]CH_{3}3OH=\frac{mass}{volume}[/tex] of [tex]\bold{CH_{3}OH}[/tex]

=64/44.8=10/7=1.43 g/l

Vapour density of [tex]\bold{CH_{3}OH}[/tex]=1.43g/l

64g of [tex]\bold{CH_{3}OH => 44.8L }[/tex]

vapour density of [tex]\small{\sf{CH_{3}3OH=\frac{mass}{volume} of } \bold{CH_{3}OH}}[/tex]

=64/44.8=10/7=1.43 g/l

Vapour density of [tex]\bold{CH_{3}OH = 1.43 g/L}[/tex]

Explanation:

a) HNO2(aq) = HNO3(aq) + H2O(l) +NO(g)

b) SoCl2 (l) + H2O (l) = So2(g) + 2HCl(aq)

c) CH4 (g) + 2O2(g) = Co2 (g) + 2H2O(g)

d) 3CuO(s) + 2NH3 (g) = 3Cu(s) + 3H2O (l) + N2(g)

Answer:

6.88 × 10^-3mol

Explanation:

Molarity = number of moles (n) ÷ volume (V)

According to this question, there in 27.5 mL of 0.250 M KOH, the number of moles of KOH can, therefore, be calculated as follows:

number of moles = molarity × volume

Volume of KOH = 27.5mL = 27.5/1000

= 0.0275L

n = 0.0275 × 0.250

n = 0.006875 mol

n = 6.88 × 10^-3mol

Answer:

A

Explanation:

Fe up to Fe+3

In the given reaction, Fe is a reducing agent. Therefore, option (A) is correct.

A substance in a redox reaction that donates its electrons to another substance and gets oxidized to a higher valency is called a reducing agent.

A reducing agent can be explained as one of the reactants of a redox reaction that can reduce the other reactant of the chemical reaction by donating its electrons.

If the reducing agent will not provide its electrons to other substances in a chemical reaction, then the reduction cannot take place. The given chemical reaction is:

Fe  +  AgNO₃  →   Fe(NO₃)₃  +  Ag

In the above reaction, the Fe is in the zero oxidation state and changes into Fe³⁺ in  Fe(NO₃)₃ after the chemical reaction So Fe losses its electron and gets oxidized. Therefore, Fe is a reducing agent in this reaction.

Learn more about reducing agent, here:

brainly.com/question/2890416

#SPJ2

Answer:

The main different of double salt and complex salt is that a double salt is a combination of two salt compounds whereas a complex salt is a molecular structure that is composed of one or more complex ions.

Answer:

1 mol of O2

Explanation:

n = m/ M

n = 32/ ( 2× 15.999)

n= 1 mol of O2

Answer:

The wavelength of the incoming photon is 172.8 nm

Explanation:

The wavelength of the incoming photon can be calculated with the photoelectric equation:

[tex] KE = h\frac{c}{\lambda_{p}} - \phi [/tex]   (1)

Where:

KE: is the kinetic energy of the electron

h: is Planck's constant = 6.62x10⁻³⁴ J.s  

c: is the speed of light = 3.00x10⁸ m/s

[tex]\lambda_{p}[/tex]: is the wavelength of the photon =?  

Φ: is the work function of the surface (Iron) = 4.5 eV        

The kinetic energy of the electron is given by:

[tex] KE = \frac{p^{2}}{2m} = \frac{(\frac{h}{\lambda_{e}})^{2}}{2m} [/tex]  (2)

Where:  

p: is the linear momentum = h/λ

m: is the electron's mass = 9.1x10⁻³¹ kg

[tex]\lambda_{e}[/tex]: is the wavelength of the electron = 0.75 nm = 0.75x10⁻⁹ m

Hence, the wavelength of the photon is:

[tex] \frac{(\frac{h}{\lambda_{e}})^{2}}{2m} = h\frac{c}{\lambda_{p}} - \phi [/tex]

[tex]\lambda_{p} = \frac{hc}{\frac{h^{2}}{2m\lambda_{e}^{2}} + \phi} = \frac{6.62 \cdot 10^{-34} J.s*3.00\cdot 10^{8} m/s}{\frac{(6.62 \cdot 10^{-34} J.s)^{2}}{2*9.1 \cdot 10^{-31} kg*(0.75 \cdot 10^{-9} m)^{2}} + 4.5 eV*\frac{1.602 \cdot 10^{-19} J}{1 eV}} = 1.728 \cdot 10^{-7} m = 172.8 nm[/tex]      

Therefore, the wavelength of the incoming photon is 172.8 nm.

I hope it helps you!        

Answer:

A.

Iron, Fe

explanation:

Iron reduces silver nitrate to silver.

Answer:

agno3

Explanation:

just took the quiz

Answer:

C6H12

Explanation:

Step 1: Find the molar mass of carbon dioxide and water

MH2O = 2(1.008) + 16.00 = 1.802x10^1 g/mol

MCO2 = 12.01 + 2(16.00) = 4.401x10^1 g/mol

Step 2: Calculate the moles of the products

nH2O = 108g / 1.802x10^1 g/mol = 5.99 or about 6

nCO2 = 264g/ 4.401x10^1 g/mol = 5.99 or about 6

Step 3: Enter moles of carbon dioxide and water into the balanced equation

CxH2x + O2 = 6CO2 + 6H2O

Step 4: Balance

We see how there is six carbon dioxide on the right side which means there are six carbons in the equation.

This means x is equal to 6 in our equation.

If you plug the information into the equation you get:

C6H12 + O2 = 6 CO2 + 6 H2O

Now all that's left is to balance the oxygens

We see how there is 18 oxygens on the right side of the equation which means there must be 18 on the left side.

Because we have oxygen gas we divide 18 by 2 which means there are 9 O2's on the left side

Therefore, the balanced equation is C6H12 + 9O2 = 6 CO2 + 6 H2O

Answer:

Coppell zinc,ironic bond

Explanation:

lt will give away two zinc atoms

Answer:

I will go with Sodium chlorine NaCl

Answer: solute separation, solvent separation, and then mixing

Explanation:

The enthalpy change of solution simply means the amount of heat which can be released or absorbed when dissolving. The enthalpy of solution is usually expressed at constant temperature in kJ/mol.

The enthalpy of solution requires three main stages:

1. Solute separation: This is when the solute is broken down. In this case, all the intramolecular forces which holds the solute together is broken.

2. Solvent separation: This is when the solvent is broken down all the intramolecular forces which holds the solvent together is broken.

3. Mixing- In this case, the solute and the solvent is mixed for a solution.

Explanation:

a) The presence of sulfate ions in a solution can be confirmed by the reaction of barium chloride in an acidic medium.

The balanced chemical equation of the reaction is shown below:

[tex]BaCl_2(aq)+CuSO_4(aq)->CuCl_2(aq)+BaSO_4(s)[/tex]

Hence, the white precipitate is barium sulfate and its formation with the ionic equation is shown below:

[tex]Ba^2^+(aq)+SO_4^2^-(aq)->BaSO_4(aq)[/tex]

b) The presence of copper (II) ions can be confirmed by the following test:

Add potassium iodide solution to copper (II) solution.

Then a white ppt of cuprous iodide along with the liberation of iodine is observed and the entire solution attains brown color.

The chemical equation of the reaction is shown below:

[tex]2CuSO_4(aq)+4KI(aq)->Cu_2I_2(s)+I_2(s)+2K_2SO_4(aq)\\[/tex]

c)(i)Due to this reaction, the blue color of the solution becomes white.

Reddish-brown copper is deposited at the bottom of the container.

(ii)In this reaction, zinc is oxidized.

d) (i) Copper is produced at the cathode.

(ii)[tex]Cu^2^+(aq)+2e^-->Cu(s)[/tex]

(iii) The reaction that takes place at the cathode is reduction.

Reduction is gaining of electrons.

Answer:

C. Fusion reactions require a lot of heat and pressure

Explanation:

A Nuclear fusion doesn't occur naturally on Earth because it requires temperatures far higher than Earth temperatures. Nuclear fusion takes place only at extremely high temperatures. That's because a great deal of energy is needed to overcome the force of repulsion between the positively charged nuclei.

Here, we have been given the the amount of helium to be 52 amu.

Thus,

$ \red{\leadsto}$ Hence, the number of atoms will be 13 atoms.

[tex] \\ [/tex]

Answer:

I hope this helps

Answer:

An object can store energy as the result of its position. For example, the heavy ball of a demolition machine is storing energy when it is held at an elevated position. This stored energy of position is referred to as potential energy. Similarly, a drawn bow is able to store energy as the result of its position

Answer:

you can see the attached file is scanned the same level of detail of the heart the heart and I am a little bit of an emergency you can see it on the heart the tree is the best of luck for tomorrow be in a few days and times are available in a while back and forth to be a good idea and latitude longitude of

Answer: B. forests are carbon sinks because they store carbon

Explanation:forests take up carbon from the atmosphere through photosynthesis and from organic matter through decomposition. so, forests are carbon sinks because they store carbon

Answer:

Luminosity is the amount of light that a star radiates. The size of the star and its surface temperature determine its luminosity. Apparent magnitude of a star is its perceived brightness, factoring in size and distance, while absolute magnitude is its true brightness irrespective of its distance from earth

Explanation:

Answer:

The answer is "5.18 ".

Explanation:

It's a question of chemistry. Therefore, the following solution is provided:

We will first determine the solution's pOH. The following can possible:

The concentration of Hydroxide ion [tex][OH^{-}] = 1.5\times 10^{-9}\ M[/tex]

[tex]pOH =?\\\\pOH = -\log [OH^{-}]\\\\pOH = -\log 1.5\times 10^{-9}\\\\pOH = 8.82\\\\[/tex]

Furthermore, the pH of the solution shall be established. It was provided as follows:

[tex]pOH = 8.82\\\\pH =?\\\\pH + pOH = 14\\\\pH + 8.82 = 14\\\\[/tex]

When collecting all the like terms:

[tex]pH = 14 -8.82\\\\pH = 5.18[/tex]

Therefore, the solution of pH is 5.18.

Answer:

fluorine

Explanation:

Explanation:

P_H

and

li_n

hope it helps