A student wants to determine if a

Plz help I need to bring up my grade, this will help bring up my grade !!!!!!!

BartSMP [9]

Answer:

WHY: You can abbreviate an element's electron configuration using the noble gas notation method because when you get down to the lower elements, specifically the d's and the f's, the electron configuration will be very long. The noble gas notation method is a faster answer while also being correct.

HOW: We can abbreviate an element's electron configuration by finding the last noble gas a specific element passed, for example calcium would have just passed Argon. Once you have the "address" of the previous noble gas, then you add on the difference between the element chosen and the noble gas, for example calcium would be [Ar] 4s^2.

Explanation:

3 0

3 years ago

Why is NX3 Unstable ? ...?

exis [7]

It is because of the small size and high electronegativity of nitrogen.
Nitrogen has very small size as compared to the halogens, which have much larger sizes. Due to this, they can not remain bonded to the nitrogen atom and hence are highly unstable.

3 0

4 years ago

Please help with my chemistry homework! : Fuel burns in a car engine. Describe how oxides of nitrogen are produced in a car engi

Blizzard [7]

Answer:

Your statement is right.

Explanation:

When fuels are burned in vehicle engines, high temperatures are produced. At this high temperature, nitrogen and oxygen from the air combine with each other to produce nitrogen monoxide (NO). When this nitrogen monoxide is released in the air from vehicle exhaust systems, it combines with oxygen present in the air to form nitrogen dioxide (NO2).

4 0

3 years ago

Please Help!! I WILL MARK BRAINLIEST IF CORRECT!! What type of reaction is shown below?

Vlad1618 [11]

Answer:

C) exothermic

Explanation:

The given reaction is exothermic.

N₂ + 3H₂ → 2NH₃ + ENERGY

when energy is released the reaction is exothermic and when energy is written on left side with reactant it means energy is added and reaction is endothermic.

Exothermic reaction:

The type of reactions in which energy is released are called exothermic reactions.

In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.

For example:

Chemical equation:

C + O₂ → CO₂

ΔH = -393 Kj/mol

it can be written as,

C + O₂ → CO₂ + 393 Kj/mol

8 0

3 years ago

500 mL of a solution contains 1000 mg of CaCl2. Molecular weight of CaCl2 is 110 g/mol. Specific gravity of the solution is 0. C

dangina [55]

Answer:

a) 0,2% w/v

b) r=500

c) 0,0182 M

d) 0,0145 m

e) 0,0137 equivalents

Explanation:

a) % w/v means mass of solute in grams per 100 mililiter of solution. Thus:

%w/v= $\frac{1,000 g CaCl2}{500mL}$ ×100 = 0,2%w/v

b) Ratio strength is a way to express concentration. For w/v is in 1g of solute r mililiters of solution have. Thus, r = 500 because we have in the first 1 g of CaCl₂ in 500 mL of solution.

c) Molarity is moles of solute per liter of solution, thus:

1,000 g of CaCl₂ × $\frac{1mol}{110g}$ = 9,09×10⁻³ moles of CaCl₂

500 mL of solution × $\frac{1L}{1000mL}$ = 0,500 L of solution

M = $\frac{9,09x10^{-3} moles }{0,500 L}$ = 0,0182 M

d) Molality is moles of solute per kg of solution.

Specific gravity is the ratio between density of the solution and density of a reference substance (Usually water). With a specific gravity of 0,8:

kg of solution = 0,500 L of solution × $\frac{0,8 kg}{1L}$ = 0,625 kg of solution

m = $\frac{9,09x10^{-3}moles }{0,625 kg}$ = 0,0145 m

e) In a salt, equivalents are the number of moles ables to replace one mole of charge. In CaCl₂ is ¹/₂ because with ¹/₂ moles of CaCl₂ it is possible to replace 1 mole of charges. Thus, in 1,5 L there are:

1,5 L × $\frac{0,0182 CaCl2 moles}{1L}$ × $\frac{1equivalent}{2 moles}$ = 0,0137 equivalents

I hope it helps!

7 0

3 years ago