Answer:
D) Strontium-90 atoms spontaneously emit beta particles.
Explanation:
The evidence that indicates that the nuclei of strontium - 90 atoms are unstable is that they spontaneously emit beta particles.
For every atomic nucleus, there is a specific proton to neutron ratio which ensures stability of the nucleus.
Any nucleus with a neutron/proton combination different from its stability ratio will be unstable and split into one or more other nuclei.
Strontium - 90 atoms are an example of this. To attain stability, they emit beta particles spontaneously.
WILL GIVE BRAINLIEST
at which distance from refrigerator door would a magnetic force of attraction be weakest
A 7cm
B 3cm
C 1cm
D 10cm
Answer:
10 cm
Explanation:
because the magnetic force of attraction becomes weaker from a greater distance.
Answer:
D 10cm
Explanation:
As the distance between the two objects(magnet and Ferromagnetic Metals and Alloys) increases the magnetic for will decrease
if a iron nail is kept 1cm far from a magnet then the magnet will atract it easily but if the same iron nail is kep 3cm far from the magnet then the magnet won't attract it easily .
(Ferromagnetic materials such as iron, nickel and cobalt are attracted to magnets, as well as rare-earth metals like gadolinium, neodymium and samarium.)
Hope you've understood
HELPP nowww plssss!!!!
True or false. The particulates left from combustion have the same mass as the substance that was burned. Giving Brainliest!
The study of chemicals is called chemistry.
The correct answer is true.
What is combustion?The process of burning anything in the presence of oxygen is called combustion.According to the question, the statement is right because the solid amount is converted into the gas after burning but the mass remains constant.
law of conservation of massit states that the mass of the element remains constant before and after the reaction.Hence, the correct answer is true.
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Sorry if it’s not a good pic but...What’s the answer?!?
Answer:
If the products contain 3 nitrogen atoms, then so did the reactants since overall mass is conserved in a chemical reaction.
Explanation:
so the answer is A
Please help me i am very lost
Calculate the salinity of the liquids in the table. Round your answers to one decimal place.
$\frac{\text{mass of salt}\left(g\right)}{\text{mass of solution}\left(g\right)}\times1000=salinity\left(ppt\right)$mass of salt(g)mass of solution(g) ×1000=salinity(ppt)
Sample Solution Mass of Salt (g) Mass of Solution (g) Salinity (ppt)
A
27
1000
B
15
850
C
94
2355
D
11
3796
Answer:
i think that's number D.
53.0 g of silver (1) nitrate reacts according to the reaction shown below:
AgNO3 + KCI — AGCI + KNO3
Find the theoretical yield of AgCl. If the amount of AgCl actually produced is 38.5 grams,
what is the percent yield of the experiment?
Answer:
Percent yield = 86.09%
Theoretical yield of AgCl = 44.72 g
Explanation:
Given data:
Mass of silver(1) nitrate = 53.0 g
Actual yield of AgCl = 38.5 g
Theoretical yield of AgCl = ?
Percent yield = ?
Solution:
Chemical equation:
AgNO₃ + KCl → AgCl + KNO₃
Number of moles of AgNO₃:
Number of moles = mass/molar mass
Number of moles = 53.0 g/ 169.87 g/mol
Number of moles = 0.312 mol
now we will compare the moles of AgNO₃ and AgCl
AgNO₃ : AgCl
1 : 1
0.312 : 0.312
Theoretical yield of AgCl:
Mass = number of moles × molar mass
Mass = 0.312 mol × 143.32 g/mol
Mass = 44.72 g
Percent yield:
Percent yield = (actual yield / theoretical yield) × 100
Percent yield = ( 38.5 g / 44.72 g ) × 100
Percent yield = 86.09%
chemical equation for cycloheptane (l)
Answer: C7H14 - PubChem.
Explanation:
5. Identify each of the following as an element, a mixture, or a compound.
a. aluminum foil
b. air
C. water
d. salt water
e. copper
wire
f. steel
Answer:
Aluminum foil ~ element
Air ~ mixture
Water ~ compound
Salt Water ~ mixture
Copper Wire ~ element
Steel ~ element
when a liquid is cooled the kinetic energy of the particles a)decrease b) increase c) stay the same
Answer:
a) decrease
Explanation:
Hope this will help
H2o is initially present in a state where its molecules are far apart. During a change of state, its molecules slow down. Which change of state has most likely taken place?
from a gas to a liquid
from a liquid to a gas
from a solid to a liquid
from a gas to a plasma
Answer: from a gas to a liquid
Explanation:
The change of state that has most likely taken place is from a gas to a liquid, where the molecules slow down and move closer together due to a decrease in temperature or an increase in pressure.
What are states of matter?Matter is anything that occupies space and has mass. The three fundamental states of matter are solid, liquid, and gas. Solids have a definite shape and volume, with tightly packed molecules that vibrate in place. Liquids have a definite volume but no definite shape, with molecules that can slide past one another.
Gases have neither a definite shape nor a definite volume, with molecules that are widely separated and move freely in all directions. A fourth state of matter, plasma, also exists and is formed at extremely high temperatures or by ionizing a gas. In plasma, electrons have separated from their nuclei to form a cloud of charged particles.
Other, more exotic states of matter have also been observed under extreme conditions, such as Bose-Einstein condensates and quark-gluon plasma.
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PLEASE HELP
What heat transfer is a Heater.
Answer:
All electric heaters make use of one or more of the fundamental heat transfer mechanisms – namely convection, conduction, or radiation.
For regular...
Conduction is heat transfer by direct contact, like frying an egg. Convection is heat transfer by the movement of gases or liquids, like most home furnaces, clothes dryers, or car heaters. Radiation is the transfer of heat in waves through space, like the sun or a fire.
If the common element of Fluorine-9 and one of the isotopes is Fluorine-10, what does the -10 tell us about the element and how many protons and neutrons does the element have?
flourine have 9 proton
19 neutrons and 9 electron
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Which of the following is not a chemical change?
a. paper being shredded
b. steel rusting
c. charcoal burning
d. a newspaper yellowing in the sun
Answer:
paper being shredded
Explanation:
Answer:
its A
Explanation:
The mass number of an atom is determined by ___.
1.adding the protons and electrons
2.adding the protons and neutrons
3.adding the electrons and neutrons
4. adding the protons,electrons and neutrons
You are making a temperature measurement with a lab thermometer. The increments (markings) are 1°C. You see that the temperature is about 1/3 of the way from 21°C to 22°C. How would you record this temperature? How many significant figures does it have? In what place value is the smallest certain digit? In what place value (tens, ones, tenths, etc.) is the uncertain digit?
Answer: 21.3, 3 sig figs, units certain, tenths uncertain
Explanation:
The temperature is 21.3 degrees Celsius, This temperature has 3 significant figures. The smallest certain digit is in the tenth place and the uncertain digit is in the decimal place.
What are significant figures?
The number that is given as digits is established using significant figures. A meaningful representation of numbers is carried by these digits. Frequently, significant numbers are employed in place of figures. By counting all of the values beginning with the first non-zero digit on the left, we may determine the number of significant digits. 12.45, for instance, contains four significant numbers.
Therefore, in the above observation, the temperature is 21.3 degrees Celsius, This temperature has 3 significant figures. The smallest certain digit is in the tenth place and the uncertain digit is in the decimal place.
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Are theories always Correct?
Answer:
no, theories are not always correct
would you consider alcohol as food nutrient? explain.
Answer:
Explanation:
No I would consider it a drug
Alcohol is considered a drug and doesn't fall under the category of food nutrients.
What is alcohol?Alcohol is a drink that contains ethanol. It is a type of alcohol that acts as a drug and is formed by the fermentation of fruits, grains, or sources of sugar.
Alcohol is classified as a depressant which means it slows down vital functions resulting in unsteady movement, slurred speech, and an inability to react quickly.
Alcohol overdose creates even more painful, depressant effects such as toxicity where the body vomits the poison, and finally unconsciousness, coma, or death. These reactions depend upon the quantity of consumption of alcohol and how quickly.
Alcohol is a drug that damages a person’s ability to think rationally and distorts his judgment. Alcohol affects the mind, so it can never be considered nutritious food.
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What occurs when a molecule combines with Oxygen and produces heat?
A. It dissolves
B. It precipitates
C. It Evaporates
D. it combusts
Answer:
D. it combustsExplanation:
Combustion is when fuel reacts with oxygen to release heat energy. Combustion can be slow or fast depending on the amount of oxygen available. Combustion that results in a flame is very fast and is called burning. Combustion can only occur between gases.
What is the air we breathe composed of?
Answer:
oxygen
Explanation:
The average weather conditions affecting a biome is called ____.
precipitation
tundra
temperate condition
Climate
For the balanced equation 2C6H6OS+1102=12CO+6H2O+2SO3 how many moles of C6H6OS reacted if 0.474 moles of SO3 are produced?
Answer:
0.474 moles of C₆H₆OS
Explanation:
Step 1: Write the balanced equation
2 C₆H₆OS + 11 O₂ ⇒ 12 CO + 6 H₂O + 2 SO₃
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of C₆H₆OS to SO₃ is 2:2.
Step 3: Calculate the moles of C₆H₆OS reacted if 0.474 moles of SO₃ are produced
We will use the previously established molar ratio.
0.474 mol SO₃ × 2 mol C₆H₆OS/2 mol SO₃ = 0.474 mol C₆H₆OS
Please help! Very important and will give brainliest to correct answer!
Two gas jars are connected to each other, but they are separated by a closed valve. One gas jar contains oxygen, and the other is empty. What will happen when the valve is opened?
Select one:
a. Oxygen molecules will remain in their original jar because of the very high density of the oxygen molecules.
b. Oxygen molecules will remain in their original jar because there is enough space in the original jar.
c. Oxygen molecules will spread evenly throughout both jars because of weak intermolecular forces.
d. Oxygen molecules will spread through both jars because of the high molecular weight of oxygen.
Answer:
c
Explanation:
they are a gas
Answer:
c. Oxygen molecules will spread evenly throughout both jars because of weak intermolecular forces.
Explanation:
Gases mold to take shape and fill the containers they're in.
Hope this helps :)
Why can a solution be classified as a mixture?
Both are always homogeneous.
It is made up of only one substance.
Both are made up of two substances that are not chemically combined.
Both are made up of two substances that are chemically combined.
Answer:
Both are made up of two substances that are not chemically combined.
Explanation:
Solutions can be classified as a mixture because both are made up of two substances that are not chemically combined.
A mixture is made up of the following properties:
They have an indefinite composition. Their constituents retain their physical properties. They can easily be separated into their physical constituents.Solutions share this property with all mixtures.
The constituent of a solution are not chemically combined or bonded together
Answer:
c
Explanation:
I go to k12 (or you) If you go to k12 this is correct
helpppp nowww plsss!!
Answer:
Solar energy.
Explanation:
Solar Energy,
Renewable sources are those, which can be used again and again so, solar energy is the answer.
How many moles are there in 100 grams of carbon dioxide?
Answer:
there are 8.3259093974539 moles in 100 grams of carbon dioxide
The number of moles that are in 100 grams of carbon dioxide is 2.272 g/mol. Moles can be calculated by dividing the mass by the molar mass of the compound.
What are moles?"The mole is a SI unit of measurement that is used to calculate the quantity of any substance."
The molar mass of many compounds can be calculated by dividing the mass of the compound by the number of moles of the compound. Mass is the quantity of matter of a physical body. The product of the molar mass of the compound and the moles of the substance are defined as mass.
Moles = mass / molar mass
The mass of carbon dioxide is 100 grams
The molar mass of carbon dioxide is 44.01 g/mol
Put the values in the formula of moles:
100 / 44.01 = 2.272 g/mol
Therefore, there are 2.272 g/mol of moles in 100 grams of carbon dioxide.
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Polar air masses bring warm temperature and have lower air temperature? T or F
Answer:
t? im pretty sure have a good day
Which set of coefficients will balance this chemical equation?
C2H4(g) + _O2(g) → 2C02(g) + 2H2O(g)
Answer:The answer is D.1,3
Explanation:
In Raoult’s law, what happens to the partial pressure of the solution when the mole fraction of the solvent increases?
Answer: c. it increases
Explanation:
8. The size and shape of an object are some of its....
Answer:
Characteristics...
Explanation:
I hope that's right, if not super sorry. I'm not the smartest. I tried my best if it's wrong
how many oxygen atoms are in 1 mol of CO2
Answer: 2 atoms
Explanation: A molecular formula of the compound carbon dioxide is CO 2 . One molecule of carbon dioxide consists of 1 atom of carbon and 2 atoms of oxygen.