What family contains the most<br> reactive nonmetals: halogen or alkali?

The heat exchange in chemical reactions is due to a change in:

Paha777 [63]

Answer:

B

Explanation:

This would be due to enthalpy. This is because that this where heat exchange happens in chemical reactions.

So, a positive enthalpy means that the reaction is endothermic (heat entering) and if enthalpy is negative this will be a exothermic (heat released)

Another example would be the use of atoms. This example if temperature is the factor, this means that at low temp there is less kinetic energy so low temperature. However, an increase in energy means that there is more kinetic energy in the atoms which means that more collisions occurring.

Hope this helps !!!!

Have a nice day :)

5 0

3 years ago

Which of the following apply to gases. Select all that apply.

alexira [117]

The answer is C , hope I helped

8 0

3 years ago

27. The density of nickel is 8.91 g/cm3. How large a cube, in cm3, would contain 2.00 x 10^24 atoms of nickel? Use dimensional a

jok3333 [9.3K]

Answer : The volume of the cube is, $21.88cm^3$

Solution : Given,

Density of nickel = $8.91g/cm^3$

Number of nickel atoms = $2\times 10^{24}$

Molar mass of nickel = 58.7 g/mole

First we have to calculate the moles of nickel.

As, $6.022\times 10^{23}$ atoms form 1 mole of nickel

So, $2\times 10^{24}$ atoms form $\frac{2\times 10^{24}}{6.022\times 10^{23}}=3.321$ moles of nickel

The moles of nickel = 3.321 moles

Now we have to calculate the mass of nickel.

$\text{ Mass of Ni}=\text{ Moles of Ni}\times \text{ Molar mass of Ni}$

$\text{ Mass of Ni}=(3.321moles)\times (58.7g/mole)=194.94g$

The mass of nickel = 194.94 g

Now we have to calculate the volume of nickel.

$Density=\frac{Mass}{Volume}$

$8.91g/cm^3=\frac{194.94g}{Volume}$

$Volume=21.88cm^3$

Therefore, the volume of the cube is, $21.88cm^3$

4 0

3 years ago

At 20.°C, a 1.2-gram sample of Mg ribbon reacts rapidly with 10.0 milliliters of 1.0 M HCl(aq). Which change in conditions would

Pavlova-9 [17]

Answer: (2) decreasing the concentration of HCl(aq) to 0.1 M

Explanation: Rate of a reaction depends on following factors:

1. Size of the solute particles: If the reactant molecules are present in smaller size, surface of particles and decreasing the size increases the surface area of the solute particles. Hence, increasing the rate of a reaction.

2. Reactant concentration: The rate of the reaction is directly proportional to the concentration of reactants.

3. Temperature: Increasing the temperature increases the energy of the molecules and thus more molecules can react to give products and rate increases.

(1) Increasing the initial temperature to 25°C will increase the reaction rate.

(2) Decreasing the concentration of HCl(aq) to 0.1 M will decrease the reaction rate due to lesser concentration.

(3) Using 1.2 g of powdered Mg will increase the reaction rate due to large surface area.

(4) Using 2.4 g of Mg ribbon will increase the reaction rate due to high concentration of reactants.

7 0

3 years ago

Read 2 more answers

_______ is an example for isotone. a)argon and carbon b) uranium and carbon c) carbon and boron d)sulphur and boron.

slavikrds [6]

Isotones are nuclides that have the same neutron number but a different proton number. Therefore the answer is C. boron and carbon.

3 0

2 years ago

Read 2 more answers

What family contains the most reactive nonmetals: halogen or alkali?