Answer:
[tex]\huge\boxed{\sf 1.0 \ mg}[/tex]
Explanation:
Half-life = 73 hours
Disintegration period = 6 days 2 hours = (6*24) hours + 2 hours
= 144 hours + 2 hours
= 146 hours
No. of Half lives = Disintegration period / Half-lifeNo. of Half lives = 146 hours / 73 hours
No. of Half lives = 2
Hence, there are 2 half lives passed in 6 days 2 hours.
Amount of thallium-201 left after first half-life:
= 4.0 mg / 2
= 2.0 mg
Amount of thallium-201 left after second half-life:
= 2.0 mg / 2
= 1.0 mg
Hence, the amount of thallium-201 left after 6.0 days and 2 hours is 1.0 mg.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807- The pit of an aqueous solution of NaOH is 12.9. What is the molarity of the solution?
Answer: The molarity of solution is 0.08 M
Explanation:
pH is the negative logarithm of hydrogen ion concentration. It tells abpout the acidity or basicity of a solution.
[tex]pH=-log[H^+][/tex]
also pH+pOH=14
given : pH of NaOH = 12.9
Thus pOH = (14-12.9) = 1.1
Thus [tex][OH^-]=10^{-1.1}=0.08M[/tex]
As [tex]NaOH\rightarrow Na^++OH^-[/tex]
As 1 mole of [tex]OH^-[/tex] is produced by = 1 mole of NaOH
Thus 0.08 moles of [tex]OH^-[/tex] are produced by = [tex]\frac{1}{1}\times 0.08=0.08[/tex] moles of NaOH
The molarity of solution is 0.08 M
sub-atomic particles like negatively charged electrons, positively charged
protons and electrically ________ neutrons
Answer:
neutral
Explanation:
There are three basic subatomic particles. These are;
Protons (positively charged)Electrons (negatively charged)Neutrons (neutral)A neutron has no charge unlike the proton and the electron. It is present in the nucleus and contributes to the mass of the atom.
Which of the following is a FALSE statement? *
A. Heat moves through solids by by conduction.
B. Molecules move faster in warmer substances.
C. Warm water is denser than cold water.
D. Heat moves through liquids and gases by convection.
Answer:
C: Warm water is denser than cold water
what is the difference between corrosion and rusting
Answer:
Corrosion is the process of deterioration of materials as a result of chemical, electrochemical or other reactions. Rusting is a part of corrosion and is a chemical process which results in the formation of red or orange coating on the surface of metals. ... Rust or rusting can affect only iron and its alloys.
Explanation:
Balance the following equation
_MgF2 + _Li2CO3 -> _MgCO3 + _LiF
Answer:
1 MgF2 + 1 Li2CO3 --> 1 MgCO3 + 2 LiF
Explanation:
What is the energy change per gram of ice when an iceberg composed of pure water, cp = 2.06 j/(gk, is heated from -25°c to -15°c?
Answer:
[tex]Q=20.6\frac{J}{g}[/tex]
Explanation:
Hello there!
In this case, according to the equation for the calculation of the heat during a heating process:
[tex]Q=mC(T_f-T_i)[/tex]
It is possible to compute it per gram of ice by just removing m from the equation by dividing at both sides. Next we plug in the given specific heat and the final and initial temperatures to obtain:
[tex]Q=2.06\frac{J}{g\°C}[-15\°C-(-25\°C)] \\\\Q=20.6\frac{J}{g}[/tex]
Best regards!
Which of these is a molecule?
a. Ca
b. Mg
C. Na
D.H20
NEED A QUICK ANSWER!
Which of the following statement is not true?
Answer: 2
Explanation: Greenhouse gases are very important in keeping our planet just right. If we have too many Greenhouse gases it would be too hot, but we can't eliminate all of them or it will be too cold
an substance that is being dissolved by another object?
Answer:
Solute - The solute is the substance that is being dissolved by another substance. In the example above, the salt is the solute. Solvent - The solvent is the substance that dissolves the other substance.
Explanation:
Determinar el volumen de una solución en mililitros cuya concentración es 0,3 M en ácido sulfúrico y que contiene 1,5 moles del ácido
Answer:
V = 5000 mL
Explanation:
¡Hola!
En este caso, dado que la molaridad de una solution se calcula al dividir las moles por el volume de solución en litros, es posible calcular el volumen cuando se dividen las moles por la molaridad, tal y como se muestra a continuación:
[tex]M=\frac{n}{V}\\\\V=\frac{n}{M}[/tex]
Así, podemos reemplazar la molaridad y moles dadas para obtener:
[tex]V=\frac{1.5mol}{0.3mol/L}=5L[/tex]
Que en mililitros sería:
[tex]V=5L*\frac{1000mL}{1L}\\\\V=5000mL[/tex]
¡Saludos!
3. A volume of gas at 1.65 atm was measured at 27°C and 343 mL. What will be the volume if the gas
is cooled to -12°C and the pressure is adjusted to 2.10 atm?
Answer:
Homework hint: P1V1 = nRT1 and V1, n, and R are constant. Remember to use Kelvin.
PLEASE HELP 20 PTS
what is the percent by volume of isopropyl alcohol in a solution that contains 24 mL of isopropyl alcohol in 1.1 L of water?
Answer:
[tex]2.18\%[/tex]
Explanation:
Volume of isopropyl alcohol = 24 mL
Volume of water = 1.1 L
Percentage of isopropyl alcohol is given by
[tex]\dfrac{\text{Volume of isopropyl alcohol}}{\text{Volume of isopropyl alcohol+Volume of water}}\times 100\\= \dfrac{24\times 10^{-3}}{1.1+2.4\times 10^{-3}}\times 100\\ =2.18\%[/tex]
The percent by volume of isopropyl alcohol in the given solution is [tex]2.18\%[/tex].
What is the Molar Mass of MgO?
Answer:
The answer should be 40.3044 g/mol
True or False: Energy can be created.
А
True
B
False
Answer:
False
Explanation:
Scientifically, energy can never be created or destroyed. However it can be transfered. This law is called The Law of Conservation of Energy.
My teacher didn’t explain this. Please Help Me!!
Due to their low melting points nitrogen oxygen and helium are examples of which type of matter when at room
temperatures?
A. Gas
B.liquid
C.Plasma
D. Solid
Which is a function common to both the muscular and skeletal systems?
Answer:
please give me brainlist and follow
Explanation:
In the musculoskeletal system, the muscular and skeletal systems work together to support and move the body. The bones of the skeletal system serve to protect the body's organs, support the weight of the body, and give the body shape.
Answer:
B. bending of the arm
Explanation:
help please. What type of reaction is this: barium nitrate --> barium oxide + nitrogen dioxide + oxygen
Answer:
Decomposition Reaction
Explanation:
Ba(NO₃)₂(s) ⇒ BaO(s) + N₂(g) + 3 O₂(g)
Barium nitrate decomposes into the chemical species that were used to create it.
What variable represents thermal energy in the equation Q = mcΔT?
A.
The variable c
B.
The variable Q
C.
The variable T
D.
The variable m
Answer:
The variable Q
Explanation:
i just took the test and got it right.... i hope this helps :)
The variable Q represents thermal energy in the equation Q = mcΔT. Hence, option B is correct.
What is specific heat capacity?The specific heat capacity is defined as the quantity of heat (J) absorbed per unit mass (kg) of the material when its temperature increases by 1 K (or 1 °C), and its units are J/(kg K) or J/(kg °C).
Q = mcΔT
Q = heat energy
m = mass
c = specific heat capacity
ΔT = change in temperature
Hence, option B is correct.
Learn more about specific heat capacity here:
brainly.com/question/2530523
#SPJ2
Explain why has a higher boiling point than NH3
Explanation:
Melting point = -33.34°cboiling point=77.73°cA new organism is discovered. It is multicellular, heterotrophic, and does move on its own. To which two kingdoms could the organism belong?
Answer:It is a plant
Explanation:
A new organism is discovered. It is multicellular, heterotrophic, and does move on its own. The organism belong to Kingdom Animalia.
What do you mean by heterotrophs ?A heterotroph is an organism that obtains energy and nutrients from other plants or animals. The term is derived from the Greek words hetero, which means "other," and trophe, which means "nourishment."
Fungi are multicellular, heterotrophic eukaryotes with chitinous cell walls. Kingdom Plantae contains autotrophic organisms with cellulosic cell walls, whereas Kingdom Animalia contains heterotrophic organisms without cell walls.
Animalia is a kingdom of multicellular, heterotrophic organisms. This kingdom includes humans and other primates, as well as insects, fish, reptiles, and a variety of other animals.
Thus, The organism belongs to Kingdom Animalia.
To learn more about the heterotrophs, follow the link;
https://brainly.com/question/25846728
#SPJ6
If you were traveling from Earth to Neptune in a spaceship, what would
you see between Mars and Jupiter?
Imposters
little green men
Pluto
the asteroid belt
Answer:
I believe it would be Asteroid Belt
Explanation:
little green men and imposters seem very unlikely, and Pluto is definetely not between earth and Jupiter
Answer:
the asteroid belt
Explanation:
it orbits between mars and jupiter
Uma peça de metal de formato irregular feita de uma liga particular foi galvanizada com zinco usando uma solução de Zn(NO₃)₂. Quando uma corrente de 2,70 A foi usada, levou exatamente 1 hora para depositar uma camada de 0,015 mm de zinco na peça. Qual é a área total de superfície da peça? A densidade do zinco é de 7,14 g /cm³. Suponha que a eficiência seja 100%. MM (Zn) = 65,4 g/mol; 1 mol e = 96500 C.
Which indicator would show a pH change from 6 to 7? A. Red litmus indicator B. Methyl red indicator C. Phenol red indicator D. Blue litmus indicator
Please legitimate answers only
Answer:
The correct answer is Choice C.
(Phenol red indicator.)
Explanation:
Phenol red indicator is an organic dye that acts as an acid-base reaction indicator in the pH range of 6.8 to 8.4.
In acidic solutions, the color is purple, and in simple solutions, the color is red.
Hope this helps!
Please mark me as Brainlinieast.
Answer:
phenol red indicator
Explanation:
Predict Will you find starch in a plant leaf grown in the light? Why?
Answer:
You would find starch in a plant leaf.
Explanation:
This is due to the fact that when there is excess energy, it will be stored in plant tissue as starch.
HELP 15-21 PLEASE!!!
Answer:
15. Lead (II) chloride
16. potassium chloride
17. Lithium oxide
18. Arsenious trioxide
19.Phosphorus tribromide
Explanation:
Answer:
ANSWER
Explanation:
help cococococo cococococo doing this for the points or whatever it is cococo
Answer:
what is cocococococo?
Explanation:
isnt it like a plant for choclate?
Answer:
hhhhhhhh
Explanation:
What element is being oxidized in the following redox reaction? Pb 2+(aq) + NH4 +(aq) - Pb(s) + NO3 (aq)
A. H
B. Pb
C. N
D. O
Occurs in many complex organisms such as plants, animals and fungi
Answer:
DNA
Explanation:
The eukaryotic cell participates in the formation of complex organisms and contains a nucleus, cytoplasmic organelles, and a cytoskeleton.
In a eukaryotic cell, DNA is contained in a compartment called the nucleus, which is enclosed by a membrane.The answer should be DNA based on the wording of the question. Hopefully this helped a little bit.
Weight is the measure of gravity on an object measured by a weight in Newtons. Weight changes if gravitational force changes.
Mass is the amount of kilogram in an object measured by a __________ in grams and does not change…it stays the _________.
Mass is an intrinsic property of matter and is measured in kilograms. The mass of a bird is a constant. A 15-gram bird is 15 grams, whether measured on the Earth, the Moon, or Mars. Weight is a measure ofthe force of gravity on a physical object and is measured in newtons.
Collision theory states that when two molecules collide with each other with sufficient energy and hit in the proper orientation, a
bond is formed. Which action will increase the rate of reaction in a closed container?
A)
adding an inert gas
B)
expand the volume
C)
increase the temperature
D
decrease the concentration
Answer:
c increase the temperature
Explanation: