Answer:
12 grams
Explanation:
For any radioactive substance
the amount of substance left after n half life is given by = [tex]x/2^n[/tex]
where x the original amount of substance.
____________________________________________
Half life of isotope Np-238 = 2 days
total no of days = 6
no of half life =total no of days/Half life of isotope Np-238 = 6/2 = 3
thus,
for our problem n = 3
initial amount of Np-238 = 96 grams
thus,
the amount of substance left after 3 half life = 96/2^3 = 96/8 = 12 grams.
Thus, 12 grams will be left after six days.
Why do more gas bubbles mean the gold is less pure
Answer:
Most likely it decreases the quality of the gold.
Explanation:
A student wants to find the volume of a rock. the student starts with 25ml of water in their graduated cylinder that water level rises to 37ml. what is the volume of the rock?
Answer:
12 ml
Explanation:
the answer will be calculated by subtracting 37 ml from 25 ml so ,
37 - 25
= 12 ml
I need help with 2, 3, and 4 please help i will give the brainliest
Answer:
2=2.28*10^5
3=3.98*10^3
4=5.76*10^3
PLEASE HELP
An engineer is designing a tire for heavy machinery, which statement
describes the clearest constraint that applies to the solution?
A. It must cost the consumer less than $200 per tire.
B. It must function safely under a heavy load.
C. It must be designed so that it has an appealing appearance.
D. It must be affordable for consumers.
Answer: it’s A
Explanation:
Answer:
It's A
Explanation:
What are some of the Properties of Liquids.
Answer:
Liquids take on the shape of their container. The liquid state of matter is an intermediate phase between solid and gas. Like the particles of a solid, particles in a liquid are subject to intermolecular attraction; however, liquid particles have more space between them, so they are not fixed in position.
Explanation:
Why is creativity Important and construction scientific methods?
I
Explanation:
Sometimes it is necessary to put forth new theories to explain experimental results, Explanation:
Creativity is important to science because sometimes, it is necessary to put forth new theories to explain experimental results. Theories are explanation of scientific observations.
Answer: Without creativity, it would be difficult to come up with new methods to answer scientific questions, meaning we likely wouldn't learn anything new.
Explanation: took the quiz
Which of the following best describes an electron?
A. It has no charge and about the same mass as a proton.
B. It has a negative charge and much less mass than a proton.
C.It has a positive charge and much more mass than a neutron.
D.It has a negative charge and about the same mass as a neutron.
Answer:
It's D. because it has negative charge and same mass as neutrons
#11- i will mark 5 stars, thanks, and mark brainliest just please help me
Answer:
what is the question????
A muffin has a mass of 100g and a volume of 500cm^3. What is the density of the muffin
Answer:
d = 0.2 g/cm³
General Formulas and Concepts:
Density = mass / volume
Explanation:
Step 1: Define
m = 100 g
V = 500 cm³
d = ?
Step 2: Find density
Substitute: d = 100 g/500 cm³Evaluate: d = 1/5 g/cm³Evaluate: d = 0.2 g/cm³Question 5 of 10
SO3 is an empirical formula for which of the following?
A. S04
B. S203
C. S402
D. S206
Is this isotope stable or radioactive?
Answer:
radioactive
Explanation:
becasue i said so. Periodt
Answer:
An unstable isotope emits some kind of radiation, that is it is radioactive.
Explanation:
How do the scientists Mendeleev and Moseley differ on their arrangement for the periodic table? A) Their periodic table was arranged the same. B) Moseley arranged the elements based on atomic masses while Mendeleev arranged the elements based on atomic number. C) Moseley arranged the elements based on atomic numbers while Mendeleev arranged the elements based on atomic masses. D) Moseley arranged the elements based on the number of protons while Mendeleev arranged the elements based on x-ray frequency.
Answer:
C is correct
Explanation:
the person above me is also correct hope this helps
The key difference between Dmitri Mendeleev and Henry Moseley's periodic table arrangements lies in the fundamental basis of their organization: C) Moseley arranged the elements based on atomic numbers while Mendeleev arranged the elements based on atomic masses.
Dmitri Mendeleev (1869): Mendeleev's periodic table was the first successful attempt at organizing the elements. He arranged the elements in order of increasing atomic masses and grouped them based on their chemical properties. Mendeleev's periodic table also left gaps for elements that were yet to be discovered, predicting their properties based on the trends of the known elements.
Henry Moseley (1913): Moseley's contribution to the periodic table was the realization that the atomic number (number of protons in the nucleus of an atom) was a more fundamental property than atomic mass. Moseley proposed that the periodic table should be arranged based on increasing atomic numbers rather than atomic masses. This arrangement resulted in a more accurate and systematic organization of the elements.
Learn more about atomic masses from the link given below.
https://brainly.com/question/29117302
#SPJ6
Does the number of molecules change when a substance changes state?
Answer:
Molecules do't break up and reform when a substance boils and cools. Particles stay the same size and shape during state changes.
Explanation:
brainliest will be appreciated
How did Moseley establish a more accurate periodic table?
HELP ME PLZ!ASAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
help me, please, i need it
Answer:
I think the answer would be C.
Explanation:
Microwaves emit radiation onto the leftover food, meaning the heat transfers to it through radiation.
what is the answer for that ,I need it ASAP !
Answer:
A molecule of the kind normally found in living systems.
Organic molecules are usually composed of carbon atoms in rings or long chains, to which are attached other atoms of such elements as hydrogen, oxygen, and nitrogen.
Explanation:
i'm really smart.
Which processes contribute to the formation of chemical sedimentary rocks?
Answer: the answer is B: Minerals dissolve and crystallize! :D
Explanation: hope this helps!
will ya'll help me, please
Answer:
Either A or D
But i think D
hope this helps =3
sorry if im wrong
What is the density of a substance with a mass of 1.8 kg and a volume of 0.2 L?
Hurry Quick for 10 points
giveaway
Answer:
The answer is 9.0 kg/LExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass = 1.8 kg
volume = 0.2 L
We have
[tex]density = \frac{1.8}{0.2} \\ [/tex]
We have the final answer as
9.0 kg/LHope this helps you
Answer:
knkjhhg
Explanation:
what is a rule for determining the atomic mass of an atom or ion ?
Answer:
Mass = Number of neutrons + Atomic number (aka number of protons)
Explanation:
Which is the most polar molecule?
1. CF4
2. BF3
3. Ar
4. H2O
5. CO2
6. CH
A 4.86 g piece of metal is placed in a graduated cylinder containing 15.5 mL of water the water level rose to 17.3 mL what is the density of the metal
Answer:
The answer is 2.70 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question
mass = 4.86 g
volume = final volume of water - initial volume of water
volume = 17.3 - 15.5 = 1.8 mL
So we have
[tex]density = \frac{4.86}{1.80} \\ [/tex]
We have the final answer as
2.70 g/mLHope this helps you
Which of the following is the correct name for N2S5?
many reactive chemicals are stored in containers filled with Argon gas for safekeeping what about Argon's atomic structure makes it safe to store reactive chemicals in?
Answer:
Argon has 8 valence electrons making it non reactive.
Explanation:
Reactive chemicals are store in containers filled with Argon gas because the argon gas is non reactive. This is true because the argon gas has completely filled octet structure.
This can further be explained by writing the electronic configuration of argon.
The electronic configuration of argon is given below:
Ar (18) => 1s² 2s²2p⁶ 3s²3p⁶
Valence electron => 3s²3p⁶ = 2 + 6 = 8
From the above illustration, we can see that the outermost shell (i.e 3s²3p⁶) is having 8 electrons indicating that it is completely filled as the maximum number of electrons any shell can accommodate outside the first shell is 8 electrons. Thus, argon has 8 valence electrons ( i.e electrons in the outermost shell) and hence it is non reactive as the outermost shell is completely filled.
In a system with 4 atoms and 1 lone pair, predict whether the lone pair will be in a B site or an A site? Explain.
Answer:
B
Explanation:
The compound corresponds to a molecule AX4E where A is the Central atom, X are the other atoms present and E is the lone pair of electrons.
The shape of this molecule is based on a trigonal bipyramid since the molecule contains five electron domains.
Since there are four bond pairs and one lone pair, the molecular geometry is see-saw with equatorial bond angle <120° and axial bond angle <90°.
For AX4E (five electron pairs), the lone pair should occupy an equatorial position instead of an axial position since the equatorial position has two neighboring electron pairs that are positioned at about 90° apart from each other and two other neighboring electron pairs that are positioned at 120° from each other. The axial position has 3 neighboring electron pairs positioned at 90° from each other and another neighboring electron pair positioned at 120°. Hence the equatorial position experiences lesser repulsion compared to the axial position.
Hence in the structure pictured in the question, position B is a preferred position for the lone pair instead of position A.
PLEASE HELP!!!!!
How much energy is needed to raise the temperature of 2.5 L of water from 20 C to 50 C? (anwer must be in Joules)
Answer:
8368 Joules
Explanation:
3 examples of substance that are soluble in water?
Answer:
salt, rocks, blah
Explanation:
Answer:
We call substances that dissolve in water soluble. Sugar and salt are examples of soluble substances. You'll need Transparent containers – test tubes or beakers. Water ( warm and cold ) Substances to try to dissolve eg. sugar, coffee, pepper, sand, flour, salt.Explanation:
Hope this helps(PLEASEE HELPPP) A topographic map of part of Arizona is shown below which of the labeled points on the map has the steepest slope?
A) 1
B) 3
C) 2
D) 4
Answer:
I think A is the answer Hope I'm right
The molarity of 8 grams of an aqueous solution of sodium hydroxide in 2 liters of solution is what?
Answer: 0.125
Explanation:
8g divided by 39.997. Then divide that answer by 2.
Answer:
0.1 M
Explanation: