1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
sveticcg [70]
3 years ago
11

The electron configuration of an element is 1s^22s^1. How many valence electrons does the element have?

Chemistry
2 answers:
Gekata [30.6K]3 years ago
7 0

The answer Would be two

lakkis [162]3 years ago
7 0

Answer : The number of valence electron present in an element is, 1

Explanation :

Electronic configuration : It is defined as the representation of electrons around the nucleus of an atom.  

Number of electrons in an atom are determined by the electronic configuration.

Atomic number : It is defined as the number of electrons or number of protons present in a neutral atom.

The given electronic configuration of an element is,

1s^22s^1

That means, the element has 1 valence electrons.

You might be interested in
A certain drug has a half-life in the body of 3.5h. Suppose a patient takes one 200.Mg pill at :500PM and another identical pill
tekilochka [14]

Answer:

The amount of drug left in his body at 7:00 pm is 315.7 mg.

Explanation:

First, we need to find the amount of drug in the body at 90 min by using the exponential decay equation:

N_{t} = N_{0}e^{-\lambda t}

Where:

λ: is the decay constant = ln(2)/t_{1/2}

t_{1/2}: is the half-life of the drug = 3.5 h

N(t): is the quantity of the drug at time t

N₀: is the initial quantity

After 90 min and before he takes the other 200 mg pill, we have:

N_{t} = 200e^{-\frac{ln(2)}{3.5 h}*90 min*\frac{1 h}{60 min}} = 148.6 mg

Now, at 7:00 pm we have:

t = 7:00 pm - (5:00 pm + 90 min) = 30 min

N_{t} = (200 + 148.6)e^{-\frac{ln(2)}{3.5 h}*30 min*\frac{1 h}{60 min}} = 315.7 mg    

Therefore, the amount of drug left in his body at 7:00 pm is 315.7 mg (from an initial amount of 400 mg).

I hope it helps you!

3 0
3 years ago
Nitrogen monoxide and water react to form ammonia and oxygen, like this: (g)(g)(g)(g) Write the pressure equilibrium constant ex
xxTIMURxx [149]

Answer:

Kp = \frac{P(NH_{3}) ^{4} P(O_{2}) ^{5}}{P(NO) ^{4} P(H_{2}O)^{6}}

Explanation:

First, we have to write the balanced chemical equation for the reaction. Nitrogen monoxide (NO) reacts with water (H₂O) to give ammonia (NH₃) and oxygen (O₂), according to the following:

NO(g) + H₂O(g) → NH₃(g) + O₂(g)

To balance the equation, we add the stoichiometric coefficients (4 for NH₃ and NO to balance N atoms, then 6 for H₂O to balance H atoms and then 5 for O₂ to balance O atoms):

4 NO(g) + 6 H₂O(g) → 4 NH₃(g) + 5 O₂(g)

All reactants and products are in the gaseous phase, so the equilibrium constant is expressed in terms of partial pressures (P) and is denoted as Kp. The Kp is expressed as the product of the reaction products (NH₃ and O₃) raised by their stoichiometric coefficients (4 and 5, respectively) divided into the product of the reaction reagents (NO and H₂O) raised by their stoichiometric coefficients (4 and 6, respectively). So, the pressure equilibrium constant expression is written as follows:

Kp = \frac{P(NH_{3}) ^{4} P(O_{2}) ^{5}}{P(NO) ^{4} P(H_{2}O)^{6}}

6 0
3 years ago
If an object is accelerating the forces acting on the object are ?​
belka [17]

Answer:

If an object is accelerating the forces acting on the object are BALANCED.

Explanation

if an object is moving at a constant rate of acceleration, the the forces acting upon it are balanced .

7 0
3 years ago
What combination of forces was the closest match? Why?
Virty [35]

Answer: COMBINED FORCES

When forces act in the same direction, they combine to make a bigger force. When they act in opposite directions, they can cancel one another out. If the forces acting on an object balance, the object does not move, but may change shape.

Explanation:

8 0
3 years ago
A substance with a mass of 50.0 g has a temperature change of 40.0
grigory [225]

Answer:

Mass=50.0g

H=670J

change in temperature=40

using. c=h÷m×change in temperature

c=670÷50×40

C=670÷2000

C=0.335jkg-1k-1

7 0
2 years ago
Read 2 more answers
Other questions:
  • What is the % yield of CO2 if 10g of CO produces 12.8 g CO2? <br> 2CO + O2 → 2CO2
    6·2 answers
  • What three factors affect the rate of dissolution?
    14·1 answer
  • How does the hydrosphere lithosphere atmosphere and biosphere work
    6·1 answer
  • The combustion of methane(CH4) produces carbon dioxide and water. Assume that 2.0 mol of CH4 burned in the presence of excess ai
    14·1 answer
  • When does the composition of a substance does not change?
    12·1 answer
  • Complete the following precipitation reaction with balanced molecular, total ionic, and net ionic equations. Remember to include
    11·1 answer
  • Comets _____. orbit the Earth are usually found between Jupiter and Mars have very irregular shapes have very elliptical orbits
    8·1 answer
  • Hello! Could somebody please help? Thanks!! Will give brainliest and 38 points!!!
    5·2 answers
  • As part of an investigation, students combined substances in a beaker to observe chemical reactions. They performed two procedur
    10·2 answers
  • Question 3 (2 points)<br> The electromagnetic waves with the lowest frequency are ______ waves.
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!