Explanation:
so for this one u need to remember this equation and use it to find out moles= mass /mr . Mr of helium is 4
so moles= mass /mr
=100/4
=25 moles
hope this make sense:)
Which best describes the velocity of a person on a merry-go-round? * 1 point zero constant increasing continuously changing
Answer:
continuously changing
Explanation:
The velocity of a person on a merry-go-round can best be described as continuously changing. This is because the initial velocity before the ride starts would be 0. Once the ride begins, it keeps going faster and faster until it reaches a certain speed. During this time the velocity is increasing. Then it remains constant for a certain period of time and when the ride is over the velocity and speed begins to decrease until ultimately reaching a speed of 0. Therefore, it is continuously changing throughout the duration of the ride.
How many days does it take 16.Og of Gold-198 to decay to 1.0g? (each half-
life = 2.69 days) *
O 10 days
0 2.69 days
O 10.76 days
16 days
PLZ HELP NOW
Answer:
10.8 days (3 sig.figs.)
Explanation:
All radioactive decay is 1st order decay defined by the expression A = A₀e^-kt
which is solved for time of decay (t) => t = ln(A/A₀) / -k
A = final weight = 1.0 gram
A₀ = initial weight = 16.0 grams
k = rate constant = 0.693/t(1/2) = 0.693/2.69 days = 0.258 days⁻¹
t = ln(1/16) / -0.258da⁻¹ = (-2.77/-0.258) days = 10.74646792 days (calculator)
≅ 10 days (1 sig. fig. based on given 1 gram mass)
A gas occupies 3.00 L at standard temperature. The volume at 350 C is 6.84 L.
True
False
Answer:
TRUE
Explanation:
Standard temperature is 273K and 350°C is 623K.
V/V' = T/T'
3/6.84 = 273/T'
T' = (273×6.84)/3
=> T' = 623K
So it is true.
name an appropriate drying agent for hydrogen gas
Answer:
Sjjejwhsshw
Explanation:
Sssskeo1jshi1bdi kwn ieni, nei, nei nei nei neox3nixnec
True or False: invasive species are native species that do no cause economic or environmental harm to the ecosystem.
Answer:
False
Explanation:
They do cause harm.
what are the moon phases. but be more detailed and don't put in "the phases of the moon" be more detailed.
Explanation:
The lunar phase or Moon phase is the shape of the Moon's directly sunlit portion as viewed from Earth. The lunar phases gradually change over a synodic month as the Moon's orbital positions around Earth and Earth around the Sun shift.
On a camping trip, Marta roasts a marshmallow in the campfire. The marshmallow grows, and then turns black.
Marta notices that the roasted marshmallow smells and tastes differently than the uncooked marshmallows. What
change has taken place, and how does Marta know?
A
a chemical change because the marshmallow changed in taste, color and smell
B
no change because the marshmallow is not a new substance
с
only a physical change because the marshmallow changed size
D
a chemical change because the marshmallow only changed in pH level
Answer:
the answers for the quiz are;
1: A. appearance, composition
2: C. they link up in different ways
3: A. Shape
4: B. false
5: C. a chunky solid formed from two liquids combining
6: B. honey dissolving in tea
7: C. a red candy dissolves and turns water pink
8: liquid water becoming steam
9: D. A substance has changed chemically
10: A. a chemical change because the marshmallow changed in taste, color and smell
Explanation:
On the roasting of marshmallows, a chemical change takes place which changed their taste, color, and smell. Therefore, option (A) is correct.
What is the chemical change?A chemical change is a type of change in which the molecular composition is altered and a new substance is formed is known as a chemical change.
The changes are irreversible and permanent in chemical change. The mass of the substance is altered by adding or removing it during a chemical change.
During a chemical change, there is an energy difference in the breaking of old bonds and the formation of new bonds.
When marshmallows are roasted, a chemical change takes place. The heat causes a chemical reaction producing water molecules, which evaporate and leave carbon behind.
The marshmallow swells as the moisture inside expands, which causes the marshmallow to swell. when the moisture expands, it forms tiny holes in the marshmallow, which offer the moisture to escape as steam.
Then, the carbon present in sugar burns with the oxygen in the air. The blackened part of the marshmallow is the roasted carbon which changes the marshmallow's color.
Learn more about chemical change, here:
https://brainly.com/question/23693316
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12.7 grams of magnesium chloride is dissolved into water in a flask and set aside for an experiment. The scientist forgets about the solution and the sunlight evaporates it. She needs at least 11 grams of magnesium chloride to continue the experiment. Will she be able to recover enough magnesium chloride from the original flask to continue the experiment
Answer:
Yes, she will be able to recover enough magnesium chloride from the original flask to continue the experiment
Explanation:
The solution prepared by the scientist contains 12.7g of magnesium chloride. The sunlight will evaporate only the water present. When the volume decreases, the magnesium chloride precipitates. When all water evaporates, all the solute, magnesium chloride precipitates totally.
That means she will recover the 12.7g of magnesium chloride.
Answer: Yes, she will be able to recover 12.7g in the flask
Explanation: Founders Educere answer
. Which one is formed by the combination of many tissues?
Answer:
organs is the right answer
Explanation:
An organ is a structure that is composed of at least two or more tissue types and performs a specific set of functions for the body. Many organs working together to accomplish a common purpose is called an organ system.
Hope that helps you bud..!
Take care..
Buhbye!
1. Do you believe we can bring an end to acid rain? How so?
2. What are some examples of land pollution?
Answer:
Emissions from Electricity. ...
Vehicle Emissions. ...
Reducing Electricity Consumption. ...
Reducing On-Road Vehicle Exhaust. ...
Other Considerations.
PLEASE HELPPPP!!!!!!
Explain the energy flowing as you hold an ice cream cone. (Be sure to mention "the system," "the surroundings," and how energy is being transferred.)
Answer:
This is what I put, it hasn't been graded though...
Within the system, the energy is flowing from your hand to the ice cream cone. Energy is also flowing from the surroundings to the ice cream cone unless it's reeeeaally cold in the surroundings in which case why are you even holding an ice cream cone when it's that cold?
Free nerve endings in the skin detect changes in skin temperature (getting warmer).
What is natural gas made of? Where does the energy and matter come from?
Answer:
a compound with one carbon atom and four hydrogen atoms (CH4).
Explanation:
Natural gas is a fossil energy source that formed deep beneath the earth's surface. Natural gas contains many different compounds. The largest component of natural gas is methane.
What do i do if i smell gas inside of the house?
Answer:
open the windows, turn off all electronics (take out all of the plugs), then find where the gas is coming from.
Explanation:
1. In which substance does bromine have an oxidation number of +3?
Answer:
The bromine atom in bromine fluoride, or BrF, has an oxidation number of +1. In bromine dioxide, or BrO2, it has an oxidation number of +4. This is because fluorine usually has an oxidation number of -1, and oxygen usually has an oxidation number of -2.
Explanation:
I got this from online so...
Define molarity of a solution.
Answer:
Molarity of a solution is defined as
the amount of a substance in a certain volume of solution or the moles of a solute per liters of a solution and also known as the molar concentration of a solution.
The units of molarity are M or mol/L
Define molarity of a solution.
Answer:Molar concentration or Molarity is a measure of the concentration of a chemical species, in particular of a solute in a solution, in terms of amount of substance per unit volume of solution.
_____
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What observation is made when magnesium powder and lead(ii) are heated together
Answer:
in the lead strip the will be no change and no reaction. this is job salvation that is made when magnesium powder and lead to our heater together
Learning Task 3: Why can a car run faster on a smooth
rood than on a rough roade (5points).
Answer:
it is easy to push a car on smooth road than on a rough road because friction is less in smooth road than on rough roads.
Answer:
Why can a car run faster on a smooth
rood than on a rough road it is because friction is less in smooth roads than in rough road....
Explanation:
hope it helps..stay safe!
Ammonium chromate is named the way it is based on being
Answer:
Ammonium dichromate is an inorganic compound with the formula (NH4)2Cr2O7. In this compound, as in all chromates and dichromates, chromium is in a +6 oxidation state, commonly known as hexavalent chromium. It is a salt consisting of ammonium ions and dichromate ions.
What is the name of this molecule?
O A. Butane
O B. Propane
O C. Propene
O D. Butene
The molecule represented below is Butane.
Important things to know about Butane Butane is an organic compound consisting of 4 carbon atoms. it is also a straight chain alkane with unsaturated bonds.its molecular formulae is C4H10.Can be used as a refrigerant.looking at the structure give each point represents a carbon atom, placing a C on each point gives you a total of 4, making it to be butane.See picture attached for a vivid illustration of butane.
Lear more about butabe here :https://brainly.com/question/1537939
Answer:
Butane
Explanation:
i just took tha test
According to the data, the temperature of the
substance is 28°C. If we know that 0°C = 273 K,
what is the temperature of the substance in
Kelvin?
Answer: 351
Explanation: From °C to kelvin we do
K=273+°C
From Kelvin to °C we do
°C=K-273 or -273+ K
What is 0.151 g in scientific notation
Answer: Scientific notation- [tex]1.51 x 10^{-1}[/tex]
Explanation: I got this by moving the decimal, so that there is one non-zero digit to the left of that decimal point. Tip- The number of decimal places you move will be the exponent on the 10.
Moved right- Negative
Moved left- Positive
What is the total number of atoms present in 5Na,PO.?
Answer:
3.01×10²⁴ atoms
Explanation:
Our compound is the Na₃PO₄
Sodium phosphate.
We assume, we have 5 moles of the mentioned salt.
1 mol of anything contains 6.02×10²³ atoms.
That's the Avogadro's number. The conversion is:
5 mol . 6.02×10²³ atoms /1mol = 3.01×10²⁴ atoms
What element was oxidized and reduced in this reaction and what is the oxidizing and the reducing agent for this reaction? Au(NO3)3 + Cu ——> Cu(NO3)2 + Au
Answer: Cu is oxidized while Au is reduced. The oxidizing agent is Au while the reducing agent is Cu
Answer:
Both blanks are "Ag"
(:
Explanation:
HELP!!!
Help,help,help,help,help, Help,help,help,help,help, Help,help,help,help,help, Help,help,help,help,help, Help,help,help,help,help, Help,help,help,help,help…
Answer:
no
Explanation:
how many grams of C are in 500g or NaHCO3
Answer: 71.43g
Explanation: The RMM of NaHCO3 is
23+1+12+16(3)=84.
There is one carbon in NaHCO3 thus there are 1×12g of C in NaHCO3.
Thus
85gNaHCO3-----12g C
500gNaHCO3---- xgram
(500×12)÷84= 71.43
What us the % composition of oxygen (O) in iron (III) hydroxide, Fe(OH)
3?
Answer:
44.91% of Oxygen in Iron (III) hydroxide
Explanation:
To solve this question we must find the molar mass of Fe(OH)3 and the molar mass of the oxygen in this molecule. Percent composition will be:
Molar mass Oxygen / molar mass Fe(OH)3 * 100
Molar mass Fe(OH)3 and oxygen:
1Fe = 55.845g/mol*1 = 55.845
3O = 16.00g/mol*3 = 48.00 - Molar mass of Oxygen
3H = 1.008g/mol*3 = 3.024
55.845 + 48.00 + 3.024 =
106.869g/mol is molar mass of Fe(OH)3
% Composition of oxygen is:
48.00g/mol / 106.869g/mol * 100 =
44.91% of Oxygen in Iron (III) hydroxideCalcium carbonate is what kind of compound?
Answer:
Chemical Compound
Explanation:
I'm not sure why but I know it's chemical. Hope this helps!
What is the definition of a commission? * 4 points Earnings based on how much they sell What you are paid to work. When you are paid to work on a mission as a coworker.
Answer:
Earnings based on how much they sell
Explanation:
A sales presentation can be defined as series of talk given by a salesperson with the attempt to persuade someone or a potential customer to buy a particular product, by giving information it. Some salespersons resort to the use of dramatics so as to initiate and close the sale of a particular product by engaging in series of theatrical actions.
In sales and marketing, the term closing with respect to a sales can be defined as the process of making a business sale successful such as through the exchange of money for a particular product or goods.
For a salesperson to be able to close a sales, he or she require abilities such as courage, negotiation skills, listening ears and interpersonal skills to do so or achieve a successful sales. After a successful sales, they're entitled to a percentage of the amount made from selling a particular product or closing a deal based on what is stated in the contract. These amount of money earned with respect to each sales is generally referred to as commissions.
Commission can be defined as an amount of money earned based on how much a salesperson sell.