Answer:
E = 3.035× 10-¹⁹J = 1.9eV
f = 4.58 × 10¹⁴Hz
Explanation:
wavelength = 6.55 × 10-⁷m
c = 3 × 10⁸m/s
f = ?
E = ?
a) f = c/wavelength
f = 3 × 10⁸/6.55 × 10-⁷
f = 4.58 × 10¹⁴Hz
b) E = hc/wavelength
E = 6.626×10-³⁴ × 3 × 10⁸/ 6.55 × 10-⁷
E = 3.035 × 10-¹⁹J
1ev = 1.6 × 10-¹⁹J
Therefore E = 3.035/1.6 = 1.9eV
The picture shows an ice cube melting.
How is thermal energy transferred in this scenario?
A. Thermal energy moves from a warmer object to a cooler object until all the substances are different temperatures.
B. Thermal energy moves from a warmer object to a cooler object until all the substances are the same temperature.
C. Thermal energy moves from a cooler object to a warmer object until all the substances are the same temperature.
D. Thermal energy moves from a cooler object to a warmer object until all the substances are different temperatures.
Answer:
B. thermal energy moves from a warmer object to a cooler object until all the substances are the same temperature
what example of matter is a mixture
Answer:
Most of the matter around us, however, consists of mixtures of pure substances. Air, wood, rocks and dirt are examples of such mixtures. Mixtures can be further classified as Homogeneous and Heterogeneous.
Physical or chemical ?
1. Starch molecules are formed from smaller glucose molecules.
2. Iron rusts
3. Ice melts
4. A match burns
5. Plants leaves lose water through evaporation
6. Hydrochloric acid reacts with sodium hydroxide to produce a salt, water and heat
7. Food is digested
8. A pellet of sodium is sliced in half
9. Proteins are made from amino acids
10. A toothpick is broken in half
ill give brainliest
Answer:
P,C,P,C,P,C,P,P,C,P
Explanation:
PLEASE HELP FAST!!! Which is a characteristic of colloids?
Which one?
A. Are homogeneous mixtures
B. Have large dispersed particles
C. Will settle out over time
D. Are made up of at least two substances
Answer:
the answer is D. Are made up of at least two
Explanation:
took the test on edge
what is the difference between a halogen and a halide?
need help urgently!
Answer:
In context|chemistry|lang=en terms the difference between halogen and halide. is that halogen is (chemistry) any element of group 7, ie fluorine, chlorine, bromine, iodine and astatine, which form a salt by direct union with a metal while halide is (chemistry) a salt of any halogen acid.
Explanation:
Answer:
When examining the periodic table, you will find that halogens are the electronegative elements in column 17, including fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). Halides are chemical compounds that contain halogens. ... Halides can be found in minerals, animals, and plants.
Hope this helps u... ^_^❤️Lithium atom of electron configuration 2,1 , it will …………. One electron to become stable ion.
lose
Gain
Share
Answer:
lose
Explanation:
as you have mentioned it has a electronic configuration as 2,1 that means it has one electrone in its last shell which is unstable. in ur mcq it has lose,gain.share
in order to be a stable atom lithium should either give away that one electron or gain 7 electrons. so as to ur question 7 electrons is out of the track so it is lose one electron
hope this helps
Please help me out with this...please
I also put the periodic table too just in case:)
Hydrogen bonds can be found between molecules of which of the following
HF
C3H8
H2
CH4
Answer:
HF
Explanation:
Hydrogen bond is one of the chemical bonds that holds atoms and molecules together. Hydrogen bonding forms between an hydrogen atom and an electronegative atom such as fluorine, oxygen, or nitrogen. These electronegative atoms pull most of the electrons from the hydrogen atom, thereby, making the molecule a polar one.
An example of molecules that forms hydrogen bonding is Hydrogen fluoride (HF). The hydrogen atom of one HF molecule is attracted to the very electronegative fluorine atom of another HF molecule due to the difference in electrons. This forms the HYDROGEN BOND in HF molecule.
What are the five properties of matter?
Explanation:
Physical Properties
color (intensive)
density (intensive)
volume (extensive)
mass (extensive)
boiling point (intensive): the temperature at which a substance boils.
melting point (intensive): the temperature at which a substance melts.
Based on atomicity , how molecules are categorized
Answer:
On the basis of atomicity, molecules can be classified as : Monoatomic-composed of 1 atom e.g. He, Ne, Ar (all noble gases are monoatomic) Diatomic-composed of 2 atoms e.g. H2 , N2 , O. Triatomic-composed of 3 atoms e.g. O
Thank you and please rate me as brainliest as it will help me to level up
the solubility of a gaseous solute _____ as the pressure on the solution ______
a. decreases, increases
b. increases, remains constant
c. increases, increases
d. increases, decreases
Answer:
B
Explanation:
True or false table salt NaC1 is a molecular compound
Answer:
If you mean NaCl is table salt than true
but if you mean NaC1 than false
Explanation:
PLEASE HELPPPPP :(
Megan likes to take hot showers before she goes to bed. She makes sure that the temperature of the water is warm enough to create steam. When she gets out of the shower, she has to wipe the mirror because there is so much water on it. Which statement best describes why there is water on the mirror?
A. The steam collected on the mirror and got cooler, causing it to condense into water droplets.
B. The steam collected on the mirror and got warmer, causing it to condense into water droplets.
C. The steam collected on the mirror and then boiled, leaving behind water droplets.
D. The steam collected on the mirror and then evaporated, leaving behind water droplets.
Answer:
A
Explanation:
what type of ions have names ending in ide?
A. only cations
B. only anions
C. only metal ions
D. only gaseous ions
What kind of metal is Calcium, and where is it found?
Answer:
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air.
Explanation:
4. Biowing a balloon is a physical and reversible change. When the balloon bursts, it is also a
physical change. Give more examples of physical change.
5. Torji blows air into a red balloon and then squeezes out the air from it. Explain why it is a
physical change.
guys plz help me
Answer: blowing a balloon is a physical change as when you blow a balloon the balloon expands but the balloon remains a balloon .there is change in Blowing a balloon is a physical change because only the size of the balloon changes , no change in chemical properties of the balloon occurs (no new substance is formed).
Explanation:
Which combination of principal energy level and sublevel
CANNOT exist?
Answer: 2d
Explanation:
Because you can not make a 2d
6) Aluminum bromide decomposes
Answer:
The reaction begins and builds up heat. This heat causes the aluminum to melt and float on top of the liquid bromine (which is producing a cloud of vapor because the heat is also boiling it). Wherever the two elements meet, sparks, heat, and light are given off.
Explanation:
be more specific
What is the molarity of a solution in which 2.34g of NaCl is dissolved in 54.2mL of water?
A.
2.52M
B.
0.739M
C.
0.0432M
D.
43.2M
Answer:
answer - b 0.739
Explanation:
I hope answer correctplease follow and like meThe temperature of 25.0 g of aluminum increases 10.0C when 222.5J of energy is added. What is the specific heat of aluminum?
Answer:
0.890J/gC
Explanation:
H=mcDeltaT --> c=H/mDeltaT
c= 222.5J/(25.0)(10.0)
222.5/250
0.890J/gC
**help** .............
Answer:
from which chapter is this question
in the formation of silicon carbide represented by the chemical equation SiO2+3C-->SiC+2CO,8.0 mole of each reactant are available for the reaction. What substance is the limiting reactant?
The limiting reactant : C
Further explanationLimiting reactant : the smaller ratio from mol and their reaction coefficient
Reaction
SiO₂+3C⇒SiC+2CO
Reactants : SiO₂ and C
mol ratio
SiO₂ :[tex]\tt \dfrac{8}{1}=8[/tex]
C :[tex]\tt \dfrac{8}{3}[/tex]
[tex]\tt \dfrac{8}{3}<8\rightarrow C~as~limiting~reactant[/tex]
Which of Newton’s Laws is demonstrated by a larger truck requiring more force to accelerate than a smaller car?
Answer:
In your science class, you will learn about Newton’s laws of motion. Do you know why these laws are so important? When you throw a baseball or you bounce a basketball on the court, you can use Newton’s laws to explain the motion of the baseball or basketball. In fact, almost all motion in the world can be explained by these laws. Newton’s laws are useful when people design airplanes, trains, cars, sports equipment, toys, and many things that have to do with motion. Some people have trouble understanding Newton’s laws of motion because it’s hard to see how the laws work without any examples. One great way to understand these laws is to look at how they relate to cars in everyday life.
The First Law of Motion
“Every object persists in its state of rest or uniform motion in a straight line unless it is compelled to change that state by forces impressed upon it.”
Can you see why it’s hard for some people to understand the first law? Those are some complicated words. To help you to understand better, let’s break it down and use the example of a car. The first part deals with an object in a “state of rest”. This means that the object is not moving. When your mom or dad parks the car in the garage or the shopping mall, the car is said to be in a “state of rest” because it is not moving. The car will not move until the engine is started and somebody drives it away. The second part deals with an object in “uniform motion”. This means that the object is moving at the same speed. When you mom or dad is using “cruise control” on a highway at 60 miles per hour, the car will be moving at that speed in a “straight line” until something happens to change it. What is this change? It depends. By using the brakes, your mom or dad can slow the car down or bring it to a stop. On the other hand, the car’s direction will be changed if it is hit by another motor vehicle.Explanation:
A. What causes these H-bonds to form? (Hint: Look at the charged regions.)
Answer:
Hydrogen bonding is caused by the tendency of some atoms in molecules to attract electrons more than their accompanying atom. This gives the molecule a permanent dipole moment , it makes it polar, so it acts like a magnet and attracts the opposite end of other polar molecules.
Explanation:
Arrange the elements in increasing order of reactivity : iron, gold, zinc, copper
Answer:
Iron, Copper, Zinc, and Gold
Explanation:
in Table of elements
Iron was no. 26
Copper no. 29
Zinc no. 30
Gold no. 79
Please help me with this question
Answer:
Explanation:
Carbon C
2. 1.5 moles of AgNO3 reacts with 0.5 mole of Mg3P2. Calculate the moles of excess
reactant that remains at the end of the reaction. Include math to justify your answer.
Answer:
No of Moles in excess at the end of the reaction is 0.25 moles
Explanation:
AgNO3 + Mg3P2 → Ag3P + Mg(NO3)2
Balancing the equation we get
6AgNO3 + Mg3P2 → 2Ag3P + 3Mg(NO3)2
6 moles of AgNO3 needs 1 mole of Mg3P2
using unitary method
AgNO3 = [tex]\frac{1}{6}*Mg3P2[/tex]
1.5 AgNO3 = [tex]\frac{1}{6}*1.5[/tex]
= 1/4 = 0.25moles of Mg3P2
So 1.5 Moles of AgNO3 requires 0.25Mg3P2 for complete reaction but we have 0.5Moles of Mg3P2 available Therefore Mg3P2 is in excess
No of Moles in excess at the end of the reaction = 0.5 - 0.25 = 0.25moles
What is the mole ratio of the following equation?
2Mg + O2 + 2MgO
O 2:1:2
O 1:2
O 2:2:2
o 2:1
**WHOEVER SOLVES THIS GETS A LOT OF POINTS
***Look at img below
Answer:
what
Explanation:
I cant see your question yet
Answer:
the question really said :
Arrange the following elements from lowest to highest ionization energy: Be, Mg, Ca, Rb, Sr
a. Be, Mg, Ca, Rb, Sr
b. Rb, Sr, Ca, Be, Mg
c. Rb, Sr, Ca, Mg, Be
d. Be, Mg, Ca, Sr, Rb
Answer:
It's (C)
Explanation:
I did research trust me I seached up the ionization energy of all of them, Be, Mg, Ca, Rb, and Sr
Since ionization energy decreases down the group and and increases across the period, the order from lowest to highest ionization energy is; Rb, Sr, Ca, Mg, Be.
In the periodic table, certain trends vary across the period and down the group. Trends like ionization energy increase across the period but decreases down the group.
Looking at the elements mentioned, the correct arrangement in order of the lowest to highest ionization energy is; Rb, Sr, Ca, Mg, Be.
Learn more: https://brainly.com/question/16243729