Answer:
D) 10.812
Explanation:
Given:
The two isotopes of boron (B).
Boron-10 has an abundance of 19.8% and Boron -11 has an abundance of 80.2%
To find:
The atomic mass of europium.
Solution:
Mass of Boron-10 = 10.013 amu
The percentage abundance of Boron-10 = 19.8%
The fractional abundance of Boron-10 =0.198
Mass of Boron-11 = 11.009 amu
The percentage abundance of Boron-11= 80.2%
The fractional abundance of Boron-11= 0.802
The average atomic mass of Boron = A.M
A.M = Mass of isotope x Fractional abundance of isotope
= 10.013amu x 0.198 +11.009amu x 0.802 = 10.81u
Therefore, D) 10.812 amu is the atomic mass of boron.
Which of the responses contains all the true
statements and no others regarding
electromagnetic radiation (light)?
¿De que dependen las propiedades del grafeno?
¿De que ha dependido el rapido avance en el desarollo de nuevos materiales basados en formas alotropicas del carbon?
POR FAVOOR ES URGENTEEEEE
Answer:
di ko maintindihan anggulo ng isinulat
in order for a circuit work there can be no _______ within the circuit?
Can you answer my question in SCIENCE... Directions: Below are the reactants and products of photosynthesis. Choose the chemical symbol that matches the word.
Answer:
Water :H2O
Carbon dioxide :CO2
Oxygen :O2
Glocuse :C6H12O6
Answer:
water = H20
carbon dioxide = CO2
oxygen = 02
glucose= C6H1206
Explanation:
Each mineral group has a distinctive chemical feature such as
a. oxides are a metal combined with oxygen
b. sulfides are a metal combined with sulfur and oxygen
c. halides are a salt combined with a metallic atom
d. phosphates are made of phosphate polygons
Answer:
A
Explanation:
5. What is a habitat?
a) An area of human development
b) A protected area for endangered species
c) The natural home or environment of an animal, plant, or other organism
d) An area where no species live
It's for science
Answer:
c) The natural home or environment of an animal, plant, or other organism
Explanation:
Please note that in order to post questions in Science, you must post in Science section, but not in History. You are asking a wrong question in the wrong section.
Thank You! Please Mark Brainliest! :)
What percentage of the Earth can a satellite reach at any given time? 100% 60% 40% 25%
Answer:
The answer should be 60%.
Answer:
40% is correct
Explanation:
please help :((
Which of the following atoms has the largest radius?
1. Na
2. H
3. Ar
4. P
5. F
6. AI
Which two elements are in the same group based on their atomic model?
Please help me with this ASAP.
Answer: 1 and 2
i think
Explanation:
What letter represents the critical temperature?
Answer:
b
Explanation:
Why are microwaves idea for transmitting satellite communication signals?
Answer:
Microwaves are best suited because
they have a higher frequency and small wavelength
Satellite communication and Earth observation from space benefit from microwaves that can pass through haze, light rain, snow, clouds, and smoke. Because they can penetrate the atmosphere, microwaves are used. Small wavelength and high frequency is employed for this.
Microwaves are radio waves with short wavelengths and frequencies in the gigahertz (GHz) range. They can send signals over great distances without any data loss thanks to their high frequency. Without producing signal overlap or interference, they may carry a wide range of frequencies.
Electromagnetic radiations include radio waves and microwaves. In communication, both are utilized. Television and radio programs are transmitted by radio waves, but mobile phones and Wi-Fi use microwaves. Radio waves are one of the several alternatives for satellite communication.
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what is the molarity of an hcl solution if 50.0 ml is neutralized in a titration by 40.0 ml of 0.400 m naoh? group of answer choices 0.200 m 0.280 m 0.320 m 0.500 m
The molarity of an HCl solution if 50.0 ml is neutralized in a titration by 40.0 ml of 0.400M NaOH is 0.320 M.
HOW TO CALCULATE MOLARITY:
The Molarity of an acid when involved in a titration procedure can be calculated by using the formula below:M1V1 = M2V2
Where;
M1 = molarity of acid (M)M2 = molarity of base (M)V1 = volume of acid (mL)V2 = volume of base (mL)According to this question,
M1 = ?M2 = 0.400MV1 = 50 mLV2 = 40 mLM1 × 50 = 0.400 × 40
50M1 = 16
M1 = 16 ÷ 50
M1 = 0.32M
Therefore, the molarity of an HCl solution if 50.0 ml is neutralized in a titration by 40.0 ml of 0.400M NaOH is 0.32 M.Learn more at: https://brainly.com/question/8732513?referrer=searchResults
which of the following statement is correct for a group of a periodic table.
i} All elements have different valency.
ii} The atomic size decrease as we move down.
iii} The electropositivity increase down the group.
iv} The electronegativity increase down the group.
Answer:
I believe it is B
Explanation:
I am on this lesson too :)
Answer:
III Electropositivity increases down the group
Explanation:
Each of these Ionic Compounds are named INCORRECTLY. 1. Find and describe the mistake 2. Correctly name the compound. CaCl2 - Calcium Chlorine CuS - Copper Sulfide Li3P - Trilithium Phosphide CuBr - Copper(II) Bromide NaOH - Sodium Hydrogen Oxide
Explanation:
The nomenclature of ionic compounds is given by:
1. Positive is written first. And if the metal atom has various oxidation states then its oxidation state is to be mentioned in brackets with help of roman numbers
2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.
1.) : Calcium chloride (Correct)
In the given compound, calcium has oxidation state of +2 and chlorine has oxidation state of -1.The name is correct.
2.) : Copper (II) oxide (Incorrect)
In the given compound,copper has the oxidation state of +1 and oxygen has oxidation state of -2.So ,the correct name will be Copper (I) oxide.
3.) : Lead (II) sulfide (Incorrect)
In the given compound, lead has the oxidation state of +4 and sulfur has oxidation state of -2. So ,the correct name will be Lead (IV) sulfide.
what is formed when the number of electrons is changed?
Answer:
Explanation:
Whether the electrons are added or given away makes no difference to the name given to parent atom -- It is called an ion which means that it has a charge. The word atom is reserved for something on the periodic table that has no charge.
Answer: Chemical bond formed when one or more electrons are transferred from one atom to another.
Explanation: Give me the brainiest
HAAAAAALP MEEEEEEEEEEE
Answer:
It would contain 10.
Explanation:
The atomic number: the number of protons.
What is the law of conservation of mass and how does it relate to chemical equations?
What does it mean for a
chemical equation to be balanced?
Answer: Matter cannot be created or destroyed in chemical reactions.
Explanation: This is the law of conservation of mass. In every chemical reaction, the same mass of matter must end up in the products as started in the reactants. Balanced chemical equations show that mass is conserved in chemical reactions.
Which element is most likely to lose electrons in a chemical reaction?
Group of answer choices
Mg
Cl
S
Br
Answer:
Write a hypothesis for Section 1 of the lab, which is about the effect the type of material has on the absorption of sunlight on Earth’s surface. Be sure to answer the lesson question: "What factors influence the absorption of sunlight at Earth's surface?"
Explanation:
As the volume of a gas at 101.3kPa changes from 30mL to 95mL the volume of the gas will?
1)Increases
2) Decreases
3 Remains the same
You measure the amount of Oxygen released when Hydrogen peroxide is reacts with Sodium Hydroxide. You are measuring a ____Change
Chemical or physical change? No links please
who can write an essay
Answer:
anyone you just have to know how
Explanation:
which group of the periodic table is composed of inert gases
Answer:
Group 0
Explanation:
A cheerful teen willing to help,
stay salty,
stay positive...
The group zero of the periodic table is composed of inert gases.They are very unreactive So, they don't form molecules easily and are found as single atoms.
Which group of metals is inert?"Noble metals, such as gold, platinum, silver, and a few rare metals. Members of this class have little or no tendency to unite with oxygen in the free state and do not change composition when placed in water at a red heat.
Noble gas atoms already have complete outer shells and have no tendency to lose, gain, or share electrons. As a result, noble gases are inert and do not participate in chemical reactions.
Because their outermost shells are completely filled, zero group elements are inert. They have no tendency to lose, gain, or share electrons with other elements.
Thus, The group zero of the periodic table is composed of inert gases because they are unreactive.
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What chemical compound is produced as a result of photosynthesis?
a
Answer: Specifically, plants use energy from sunlight to react carbon dioxide and water to produce sugar (glucose) and oxygen.
Explanation:
¿De que ha dependido el rapido avance en el desarollo de nuevos materiales basados en formas alotropicas del carbon?
Answer:
ano pong topik po yan
Which statement describes a similarity between an apple and gasoline
Answer:
They both contain chemical energy, which people and cars convert into mechanical energy.
Explanation:
Answer:
B)They both contain chemical energy, which people and cars convert into electrical energy.
Explanation:
Do the boiling points and melting points of these elements support the claim that elements of the same group have similar physical characteristics?
Answer:
Elements in the same group has different physical properties such as boiling and melting points. However there are trends of their physical properties down the group.
Explanation:
You should look at the perdoic table to for extra help
The boiling points and melting points of the given elements does not support the claim that elements of the same group have similar physical properties.
What are boiling point and melting point?The boiling point of a substance is the temperature at which it changes from liquid state to gaseous state. Melting point is the temperature at which the substance changes from solid to liquid state.
Elements in the same group shows similar physical and chemical properties. But from the boiling and melting point we cant say that they are in the same group.
Elements in a group shows a trend in boiling point and melting point but cannot be distinguished with this from other groups.
Hence, boiling point and melting point of the elements do no support for the similar properties in a group.
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Your question is incomplete, but most probably your full question was,
Do the boiling points and melting points of these elements support the claim that elements of the same group have similar physical characteristics? (image uploaded)
the nucleus or center area of the atom contains two kinds of subatomic particles. which two?
when is it appropriate to form double or triple bonds in a lewis structure?
It is appropriate to form double or triple bonds in a Lewis structure when four or six electrons are shared.
A Lewis structure is a representation of a molecule using dots to show the valence electrons in the molecule. This dots are shown around the symbols of the elements.
However, in instances where four or six electrons are shared between bonding atoms, a double or triple bond is used. A double bond means that four electrons are shared. A triple bond means that six electrons are shared.
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Help meeeeeeeeeeeeeee
Answer:
whatttttttttttttttttttttttt
Answer:
Breaking glass - chemical change
popsicle - physical
milk - chemical
bread - physical
roasting - chemical
egg - chemical
fireworks - chemical
mixing something with water - chemical
popcorn - chemical
colouring hair - physical
melting chocolate - physical
crumpled paper - physical
rusted nails - chemical
crushed can - physical
cooked egg - chemical
bending metal - physical
melting ice - physical
bleaching clothes - chemical
If u want to differentiate between chemcial and physical change u need to remember this-
physical change - no new substance is formed (Even for melting of ice it's still water) and it can be reversible, except for some cases like tearing of paper
chemical change - a new substance is formed
when it is time to end a reflux, first choose... and then turn off the heat. choose... until the system has cooled.
Answer:
second one is better
Explanation:
system is very much hot in first state..so wait for cooling down the system..but these depend on the organic compounds and products you are using. sometimes we need to carryout further steps in hot state..then you can't wail it to cool down