What is the major organic product obtained from the reaction of ethylbenzene with nitronium ion, followed by benzylic oxidation?

Energy from a reaction was determined to be 3870 J using a water calorimeter, when burning 9.00 grams of H2. What is the total

Paraphin [41]

Answer:

860 J / mol

Explanation:

Enthalpy = Energy / no. of moles

no. of moles = mass / molar mass

Take the atomic mass of H = 1.0,

molar mass of H2 = 1.0 x 2

= 2.0

no. of moles of H2 = 9.00/2

= 4.5 mol

Hence,

Enthalpy = 3870 / 4.5

=860 J / mol

7 0

3 years ago

What is the formula (with cation and anion charges) for copper (II) hydroxide?

Thepotemich [5.8K]

Answer:

Cu²⁺(OH)⁻₂

Explanation:

Step 1: Find the symbols for the substances

For copper, see your periodic table. Copper is "Cu".

For hydroxide, see your polyatomic ions chart. Hydroxide is "OH".

Step 2: Find the charges for each element.

Copper (II)'s charge is 2, which is the roman numerals in the brackets.

Hydroxide's charge is -1.

Charges are written as superscripts. You do not need to write "1".

In formulas, write the positively charged atom first.

Cu²⁺(OH)⁻ Put brackets around hydroxide because it has 2 elements.

Step 3: Write the number of atoms.

The number of atoms that an element has is the same as its partner's charge.

The charge of copper is 2, so hydroxide has 2 atoms.

The charge of hydroxide is 1, so copper has 1 atom.

Cu²⁺₁(OH)⁻₂

You do not need to write the "1" for atoms.

Cu²⁺(OH)⁻₂

8 0

3 years ago

Why does a plastic bottle is sealed at a high altitude change it’s shape when it is taken to low altitude

nadya68 [22]

Answer:

The bonds between the molecules of the plastic bottle become weaker as the altitude decreases.

3 0

3 years ago

The nonmetals helium, neon, and argon and the metals copper, silver, and gold are among only a few elements that are found in na

Fynjy0 [20]

Answer:

A pure element is a pure substance that has only one kind of atoms. If a substance is present in nature in elemental form, it means that the element is not very reactive as reactive elements exist in the form of their compounds with atoms of other elements. Element can be categorized as a metal or a non-metal based on some physical observable properties. Generally, metals are shiny lustrous solids and nonmetals are gases. Metals are good conductors of heat and electricity whereas nonmetals are not conductors.

Explanation:

Hope this helps:)

5 0

2 years ago

Hydrazine (N2H4), a rocket fuel , reacts with oxygen to form nitrogen gas and water vapor. The reaction is represented with the

lilavasa [31]

Answer:

D) 8.40 L H₂O(g).

Explanation:

The balanced equation for the mentioned reaction is:

2N₂H₄(l) + O₂(g) → N₂(g) + 2H₂O(g),

It is clear that 2.0 moles of N₂H₄ react with 1.0 mole of O₂ to produce 2.0 moles of N₂ and 2.0 moles of H₂O.

At STP, 4.20L of O₂ reacts with N₂H₄:

It is known that at STP: every 1.0 mol of any gas occupies 22.4 L.

using cross multiplication: 

1.0 mol of O₂ represents → 22.4 L.

??? mol of O₂ represents → 4.2 L.

∴ 4.2 L of O₂ represents = (1.0 mol)(4.2 L)/(22.4 L) = 0.1875 mol.

To find the no. of moles of H₂O produced:

Using cross multiplication:

1.0 mol of O₂ produce → 2.0 mol of H₂O, from stichiometry.

0.1875 mol of O₂ produce → ??? mol of H₂O.

∴ The no. of moles of H₂O = (2.0 mol)(0.1875 mol)/(1.0 mol) = 3.75 mol.

Again, using cross multiplication:

1.0 mol of H₂O represents → 22.4 L, at STP.

3.75 mol of H₂O represents → ??? L.

∴ The no. of liters of water vapor will be produced = (3.75 mol)(22.4 L)/(1.0 mol) = 8.4 L.

So, the right choice is: D) 8.40 L H₂O(g).

3 0

3 years ago