Answer:
The periodic law states “When elements are arranged in order of increasing atomic number, there is a periodic repetition of their chemical and physical properties
(1) Phosphorus silicon is a semi-conductor
When Silicone is altered with Phosphorus, 4 of its electrons form covalent bonding and the 5th electron becomes delocalized and thus it increases electrical conduction
Answer:
blue blah blue blah
Explanation:
(5) Use scientific notation, make the following conversions:
6.20 km to m
Answer:
6200 meters
Explanation:
To convert from km to m you have to multiply the number by a thousand
Answer:
6.2×10^3 m
Explanation:
6.20×1000=6200m
In scientific notation 6200 = 6.2×10^3
What is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n = 4 to an energy level with n = 2?
Answer:
[tex]4.86\times10^{-7}\ \text{m}[/tex]
Explanation:
R = Rydberg constant = [tex]1.09677583\times 10^7\ \text{m}^{-1}[/tex]
[tex]n_1[/tex] = Principal quantum number of an energy level = 2
[tex]n_2[/tex] = Principal quantum number of an energy level for the atomic electron transition = 4
Wavelength is given by the Rydberg formula
[tex]\lambda^{-1}=R\left(\dfrac{1}{n_1^2}-\dfrac{1}{n_2^2}\right)\\\Rightarrow \lambda^{-1}=1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\\\Rightarrow \lambda=\left(1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\right)^{-1}\\\Rightarrow \lambda=4.86\times10^{-7}\ \text{m}[/tex]
The wavelength of the light emitted is [tex]4.86\times10^{-7}\ \text{m}[/tex].
which element can form an oxide with the general formula m2o or mo where m is a metal
Answer:
Because the compound has a formula of M2O, the number of valence electrons of M should be 1. Therefore, (1) Group 1 is the correct answer because elements in group 1 have 1 valence electron.
Explanation:
An isotope has three forms. 30% have a mass of 4 amu, 20% have a mass of 5 amu and
50% have a mass of 3 amu, Average atomic mass will be closest to
The average atomic mass will be 3.70 amu
We have to obtain the average atomic mass by multiplying the mass of each isotope in amu by the relative abundance of the given isotope as contained in the data of the question.
Hence;
Average atomic mass;
(0.30 * 4) + (0.20 * 5) + (0.50 * 3)
= 1.20 + 1.00 + 1.50
= 3.70 amu
https://brainly.com/question/13292428
CHEMISTRY HELP
Once the following equation is balanced, what is the correct coefficient for Z₂?
Answer:
The coefficient of Z₂ is 1.
Explanation:
From the question given above:
X + ZY —> XY + Z₂
Next, we shall balance the equation to obtain the coefficient of Z₂. This can be obtained as follow:
X + ZY —> XY + Z₂
There is 1 atom of Z on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of ZY as shown below:
X + 2ZY —> XY + Z₂
There are 2 atoms of Y on the left side and 1 atom on the right side. It can be balance by putting 2 in front of XY as shown below:
X + 2ZY —> 2XY + Z₂
Now, we have 1 atom of X on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of X as shown below:
2X + 2ZY —> 2XY + Z₂
Now the equation is balanced.
Thus, the coefficient of Z₂ is 1.
A patient is prescribed 100mg/day of antibiotic for 2 weeks. The antibiotic is available in vials that contain 20mg/vial of the drug. How many vials are necessary for the entire treatment?
What is the difference between an atomic symbol and a chemical symbol?
Answer: A chemical symbol is a one- or two-letter designation of an element. Compounds are combinations of two or more elements. A chemical formula is an expression that shows the elements in a compound and the relative proportions of those elements.
What is a molecule contains the genetic instructions for the development and functioning of all living organisms found in the nucleus of a cell
What are 3 characteristics of all invertebrates
Answer:
None have backbones
No cell walls
Multicellular
Includes radial or bilateral body symmetry.
Explanation:
Identify the ionic compound that can form between potassium as the metal and nitrogen as the nonmetal.
help!!
Answer:
[tex]6K _{(s)} + N _{2(g)} = = > \:2K _{3} N _{(s)} [/tex]
Potassium nitride
9. Which of these is not a mixture? *
Solution
Alloy
Amalgam
They are all mixtures.
Answer:
They are all mixture
Explanation:
last option
find the weight of HNO_3 present in 20ml, 0.30 N
Answer:
mass of HNO₃ = 0.378 g
Explanation:
Normality = Molarity * number of equivalents
Molarity = Normality/number of equivalents
normality of HNO₃ = 0.30 N, Volume = 20 mL
HNO₃ ionizes in the following way:
HNO₃(aq) ----> H⁺ + NO₃⁻
Therefore, number of equivalents for HNO₃ is 1
molarity of HNO₃ = 0.30/1 =0.30 mol/dm³
Using the formula, molarity = number of moles/volume in liters
number of moles = molarity * volume
Number of moles of HNO₃ = 0.30 mol/dm³ * 20ml * 1 dm³ /1000 mL
number of moles = 0.006 moles
From the formula, mass = number of moles * molar mass
molar mass of HNO₃ = 63.0 g/mol
mass = 0.006 * 63
mass of HNO₃ = 0.378 g
11. Everybody loves Mr Brown
Answer:
NO I DON'T ✌✌✌✌✌✌✌✌✌
The compound sodium nitrate is a strong electrolyte. Write the transformation that occurs when solid sodium nitrate dissolves in water.
Answer and Explanation:
Since the compound sodium nitrate (NaNO₃) is a strong electrolyte, it dissociates completely into ions when is dissolved in water, as follows:
NaNO₃(s) → Na⁺(aq) + NO₃⁻(aq)
So, the solid compound produces the sodium cation (Na⁺) and the nitrate anion (NO₃-) in the aqueous medium.
What do you think the saying ‘think globally, act locally’ means? How does this apply to the issue of plastic debris in the ocean?
Will give brainliest
Give an example of chemical reaction that occurs in everyday life
Answer: metal and salt water
Explanation: salt starts to brake down metal and metal is everywhere in the ocean hope this helps
Answer:
baking a cake.
Explanation:
baking a cake is an example of a chemical reaction that happens daily because a new substance is forming when the cake is being baked. hope this helps! :)
