Answer:
a
Explanation:
Answer:
A
Explanation:
Density is the amount of space that atoms are compacted in a substance.Apr 25, 2017
ora
If a student is combining two
substances and sees bubbles and
is probably taking
fizzing, a
place.
A. chemical change
B. physical change
Answer:
A a chemical change
Explanation:
because a chemical change is when you mix tow substance together and they creat a new substance
In a living organism, the organic material contains 0.22 Bq of 14C per gram of carbon. A sample of charcoal from a campfire contains 0.055 Bq of 14C per gram of carbon. How long ago was this campfire in use? (14C half-life is 5730 yr)
Answer:
6
Explanation:
The age of the charcoal sample in the campfire in use is equal to the time taken for the decay of 0.22 of C-14 to 0.055 Bq. Hence its age is 11552.45 years.
What is radioactive decay?Unstable radioactive isotopes of atoms undergo nuclear decay by the emission of charged particles such alpha or beta particles. Radioactive decay is a first order reaction. Thus, the decay constant is written as:
k = 1/t ln (W0 / Wt)
where W0 be the initial weight and Wt be the weight after time t.
The decay constant is related to the half life time of the sample by the expression:
k = 0.693 / t1/2.
Given that t1/2 of C-14 = 5730 years.
Thus, k = 0.693 /5730 = 0.00012 yr⁻¹.
Now, we can calculate the time t using the first order equation.
t = 1/k ln ln (W0 / Wt)
= [ ln (0.22 Bq/ 0.055 Bq) ] / 0.00012 yr⁻¹
= 11552.4 years.
Therefore, the age of the sample of charcoal is 11552.4 years.
To find more on radioactive decay, refer here:
http://brainly.com/question/1770619
#SPJ2
For each of the three ionic compounds, select which main group X belongs to.
X₂PO4
Answer:group 1A(1)
Explanation:
help meeee I BEG YOU!
Which type of element Is not likely to react chemically with other elements to form a compound?
Answer:noble gases
Explanation:
E=hv h= 6.62 x 10^-34 m^2 kg/ s
What would be the energy contained in a photon of light that has a frequency of 5.0 x 10^12?
Please show work!!
v=5.0×10^12Hz
[tex]\\ \sf\longmapsto E=hv[/tex]
[tex]\\ \sf\longmapsto E=6.626\times 10^{-34}Js\times 5\times 10^12s^{-1}[/tex]
[tex]\\ \sf\longmapsto E=33.13\times 10^{-22}J[/tex]
3. What is the picture displayed? *
1 point
Captionless Image
Answer:
(not sure what's the question ) Captionless image??
Sodium chlorate decomposes into sodium chloride and oxygen gas as seen in the equation below.
2NaClO3 --> 2NaCl +3O2
How many moles of O2 were produced by 2 moles of NaClO3? Round your answer to the nearest whole number.
Explanation:
3 moles of O2 will be produced from 2moles of NaCLO3.
hope this helps you.
The electronic structure 1s22s22p63523p64523d8 refers to the ground state of
Kr.
Ni.
Pd.
Fe.
none of the above.
Previous
The given electronic configuration 1s²2s²2p⁶3s²3p⁶4s²3d⁸ is the Nickel (Ni). Therefore, option (B) is correct.
What is an electronic configuration?The electron configuration can be explained as electrons being filled in different energy levels of an atom of a particular element. In the electron configuration, the number of electrons is usually written as a superscript of atomic subshells. For example, the electron configuration of Oxygen is written as 1s²2s²2p⁴.
The sequence of fully filled subshells that correspond to the electronic configuration of a noble gas is denoted by square brackets. The principal quantum number (n) can be used to evaluate the maximum number of electrons in an electron shell.
The value of 2n² is given the maximum number of electrons. The atomic orbitals at low energy must be filled first occupying an orbital with a higher energy level.
The total number of electrons filled in the given electronic configuration 1s²2s²2p⁶3s²3p⁶4s²3d⁸ is 28. The atomic number of Nickel is 28 therefore it is the configuration of Nickel.
Learn more about electronic configuration, here:
brainly.com/question/5624100
#SPJ2
many substance are compound what is a compound
Chemical compound, any substance composed of identical molecules consisting of atoms of two or more chemical elements. All the matter in the universe is composed of the atoms of more than 100 different chemical elements, which are found both in pure form and combined in chemical compounds.
Answer:
A compound is a unique substance that consists of two or more elements combined in fixed proportions.
Explanation:
okkk
I am giving the brainliest answer too
Explain… What are the subatomic particles of an atom, and where are they located in the atom? Be specific.
Atomic Particles
Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).
I hope its helpWILL MARK BRAINLIEST!!!!!!!
WILL GET 50+ POINTS FOR ANSWERING QUESTION!
If F1 is equal to F2 and F4 is greater than F3, which statement is correct?
An unbalanced force will move the box up.
An unbalanced force will move the box down.
Several balanced forces will keep the box stationary.
Several balanced forces will keep the box moving towards the right.
"An unbalanced force will move the box down"
I could be wrong but I tried
And it's ok if you don't give brainliest to me
But I hope this helped:)
Have a wonderful day!
Helpppp meeeee!!! I beg you
Answer:
True
Explanation:
what is the answer to (x+3)=4
Answer:
1
Explanation:
x + 3 =4
subtract 3 from 4
You are left with one.
Plug in the answer
1+3=4
18) Max can lift 180 x 104 grams with ease. How much is this in pounds
Answer:
41.184 pounds
Explanation:
Calculate the total grams first.
180 x 104 = 18,720 grams
Convert that into kilograms (kg)
18,720g 1 kg
------------ X ------------- = 18.720 kg
1 1000 g
Convert kilograms into pounds.
18.729 kg 2.2 lb
--------------- X ----------- = 41.184 lb (pounds)
1 1 kg
Fill in words that correctly complete this sentence. Anna looks around the skating rink and notices many examples of the movement of thermal energy. For example, she sees her friend holding a cup of hot chocolate in the cold rink. Thermal energy flows from ( ) matter to ( ) matter.
Answer:
hot to cold matter
which of the following are examples of single replacement reactions select all that apply.
1) Ca(OH)2(aq) + 2 HCl(aq) ----> CaCl2(aq) + 2 H2O(l)
2)Mg(s) + Zn(NO3)2(aq) ------> Mg(NO3)2(aq) + Zn(s) 3)Na2S(aq) + Cd(NO3)2(aq) ----> 2 NaNO3(aq)
4) K(s) + 2HCl(aq) ----> 2KCl (aq) +H2(g)
Answer:
4
Explanation:
please mark brainiest
K(s) + 2HCl(aq) ----> 2KCl (aq) +H2(g) is an example of single replacement reactions.
What do you mean single replacement reactions?A single-displacement reaction, also known as single replacement reaction or exchange reaction, is a chemical reaction in which one element is replaced by another in a compound.
Single-replacement reactions always involve two pure elements and one aqueous compound/solution. In the above reaction, the A and C would be pure elements.
A single replacement reaction, sometimes called a single displacement reaction, is a reaction in which one element is substituted for another element in a compound.
Learn more about single replacement reactions:
https://brainly.com/question/13903783
#SPJ2
How do we calculate how fast (speed) Earth is rotating on its arist
speed = distance / time
speed = distance x time
speed = time / distance
Help with science ASAP!! Will give brainliest!! :)
- What happens when a hydrogen atom absorbs a quantum of energy?
the hydrogen moves to an excited state and electrons will move to higher energy levels
4
Select the correct answer.
Which statement best describes how chemical equations demonstrate conservation of mass?
O A.
The number of reactants is the same as the number of products.
O B.
The compounds are the same on each side of the reaction.
O c.
The number of atoms of each element is the same on each side of the equation.
OD.
The state of matter is the same on each side of the equation.
Answer:
C. The number of atoms of each element is the same on each side of the equation.
Explanation:
[tex].[/tex]
1. Since the electron has a negative electric charge and the nucleus has a positive
electric charge, where would you expect to find electrons in atoms?
What mass of H2O is produced by the combustion of 1.00 mol of CH4?
CH4(g) + 202(g) → CO2(g) + 2H2O(e)
The mass of H2O is produced by the combustion of 1.00 mol of CH4 is 36.0 grams.
What do you mean by molar mass ?The term molar mass is defined as the mass of 1 mole of that particular substance and number of grams per mole of a compound.
The balance chemical equation is as follows:
CH4(g) + 202(g) → CO2(g) + 2H2O(e)
The mass of H2O = 36.0 g
Calculating the mass of H2O produced
mass of H2O = 1.00 mol CH4 × (2 mol H2O / 1 mol CH4) × (18.015 g H2O / 1 mol H2O)
mass H2O = 36.0 grams
Thus, The mass of H2O is produced by the combustion of 1.00 mol of CH4 is 36.0 grams.
To learn more about the molar mass, follow the link;
https://brainly.com/question/12127540
#SPJ1
How much heat is necessary to 20g of water at 100*C into steam at 100*C?
Answer:
To convert 100.0 g of water at 20.0 °C to steam at 100.0 °C requires 259.5 kJ of energy.
The amount of heat which is required for a phase change of a substance without any change in temperature is known as latent heat. Here the amount of heat required is 10,800 calories.
What is heat capacity?The heat capacity of a substance or a system is defined as the amount of heat required to raise its temperature through 1°C. It is denoted by C. The specific heat capacity is the amount of heat required to raise the temperature of 1 gram of the substance through 1°C.
The equation to calculate the heat required is:
Q = mc (T₂ - T₁) + mL₁
L = Latent heat of vaporization of water
m = mass
c = specific heat capacity
T₂ = Final temperature
T₁ = Initial temperature
T₂ - T₁ = 100 - 100 = 0°C
Q = 20 g × 1 cal /g°C × 0°C + 20 g × 540 cal/g
Q = 10,800 calories
Thus the amount of heat required is 10,800 calories.
To know more about heat capacity, visit;
https://brainly.com/question/19460890
#SPJ2
how many significant figures are in 5.76 e 15
Answer: 3 significant figures
Explanation: because in scientific notation only the before and after decimal number are considered but in standard form all numbers including exponents are all significant figures
Answer:
3 significant figures
Explanation:
0's are not significant.
I hope it helps you!
[tex]GraceRosalia[/tex]
Which element in row 6 of the periodic table has the largest radius
Answer:
Cesium atomic number 55
1.-Una solución de 1600 ml contiene 9,5 gramos de agua oxigenada H2O2 Calcular el porcentaje peso volumen del soluto.
PLEASE HELP!!!!!!!!!!!!!
Which option would be an appropriate model of nuclear fission?
A. dividing a stack of paper equally between two people
B. taking a teaspoon of sugar from a bowl
C. disturbing a drop of water such that it breaks into smaller droplets
D. cutting a cake in half
Answer:C
Explanation:
Can anyone help me with this?
Answer:
Label 2
Explanation:
Earth is about 2/3 of the way up the Orion Arm of the Milky Way Galaxy
Gaseous butano (CH,(CH),CH) will react with gaseous oxygen (0) to produce gaseous carbon dioxide (CO2) and goseous woter (11,0). suppose
20.9 g of butane is mixed with 54, 9 of oxypen. Calculate the minimum mass of butone that could be left over by the chemical reaction. Be sure your answer
has the correct number of significant digits.
Answer:
Firstly, We have to convert it in the Miles formula...
No. of moles = Mass given/Molar Mass
So, the final answer be come
Ans - 50.8 gm and there same % is 50.8% butane in reaction