Answer:Within the flower, sperm cells are produced by pollen at the tips of stamens, while egg cells develop in ovules, tiny structures embedded in the ovary at the base of the pistil.
I didn't realize the person up top had the same answer give them the brainliest! :)
radium 226 has a half life of 1600 yers. suppose we have a 300g sample. how much remains after 200 years
Answer:
[tex]A=275.1g[/tex]
Explanation:
Hello.
In this case, since the radioactive decay is computed via:
[tex]A=A_0*2^{-\frac{t}{t_{1/2}}[/tex]
For the initial amount of Ra-226 (300 g), once 200 years have passed, the remaining mass is:
[tex]A=300g*2^{-\frac{200years}{1600years}}\\\\A=275.1g[/tex]
This is, considering that the half-life is 1600 years, it means that the mass of Ra-226 is decreased.
Best regards.
Answer the following questions in the space provided.
1. Classify each of the following as a homogeneous or heterogeneous substance.
a. iron ore
b. quartz
c. granite
d. energy drink
e. oil-and-vinegar salad dressing
f. salt
g. rainwater
h. nitrogen
2. Classify each of the following as a physical or chemical change.
a. ice melting
b. paper burning
c. metal rusting
d. gas pressure increasing
e. liquid evaporating
f. food digesting
3. Compare a physical change with a chemical change.
Answer: iron ore is heter
quartz homo
granite heter
energy drink homo
oil-and vingar salad dressing heter
salt homo
rainwater homo
nitrogen homo
ice melting chemical
burning paper chemical change
i need help please help me now please
Which organism on the geologic time scale are now extict
Answer:The Ordovician and Cambrian Periods are referred to as the "age of invertebrates", with trilobites abundant. In this period, brachiopods became more abundant that the trilobites, but all but one species of them are extinct today.
Explanation:
In Natural selection, individuals whose unique characteristics are well-suited for an environment tend to survive and produce more offspring. true or false?
Answer: True
Explanation:
All of the following changes to a metal are physical changes except_____.
bending
melting
rusting
polishing
Answer:
D)Polishing..
Answer:
Wouldn't it be rusting
Explanation:
Melting and bending are physical changes so is polishing. so rusting is the only choice, for metal to rust wouldn't it need a chemical change.
Which is not a compound?
a. carbon dioxide gas
b. oxygen gas
c. silicone dioxide
d. water
Answer:
The answer is b oxygen gas b/c its an element
Explanation:
Which of the following substances will dissolve in water? Check all that apply.
Magnesium Sulfate
Methane
Butane
Sodium nitrate
Answer:
The answers are A. and D.
According to the concept of solubility and properties of ionic compounds, magnesium sulfate and sodium nitrate dissolve in water.
What is solubility?Solubility is defined as the ability of a substance which is basically solute to form a solution with another substance. There is an extent to which a substance is soluble in a particular solvent. This is generally measured as the concentration of a solute present in a saturated solution.
The solubility mainly depends on the composition of solute and solvent ,its pH and presence of other dissolved substance. It is also dependent on temperature and pressure which is maintained.Concept of solubility is not valid for chemical reactions which are irreversible. The dependency of solubility on various factors is due to interactions between the particles, molecule or ions.
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A element is having atomic number 82. find the number of its protons and electrons
Answer:
The number of its protons and electrons are 82 each
Explanation:
Atomic no of an element = 82
Atomic no = No of protons
⇒ No of protons = 82
Electrons are negatively charged particle and Protons are positively charged particles.
No of electrons = 82
Hence, the element is Lead with 82 protons and electrons
Which of the following compounds is the MOST polar?
H−Br
H−F
H−Cl
H−I
Identify the placement of items A-E using the drop-down menus.
A)
⇒No
⇒Yes
B)
⇒No
⇒Yes, when liquid or solution
⇒Yes, when solid
C)
⇒No
⇒Yes
D)
⇒No
⇒Yes
E)
⇒No
⇒Yes
Answer:
A=no
B= yes when liquid or solution
C=yes
D=no
E=yes
Explanation:
According to the given table, the placement of items A-E are
A) ⇒ No
B) ⇒Yes, when liquid or solution
C) ⇒Yes
D) ⇒No
E) ⇒Yes
What is conductivity and Malleability?
Malleability - Those metals that can be beaten into thin sheets with a hammer or any heavy object. For example - Cu, Au etc
Conductivity - Conductivity is the measure of the ease at which an electric charge or heat can pass through a material. For example - Metals are good conductors of heat and electrolytic solution is conductors of electricity.
Therefore, according to the given table, the placement of items A-E are
A) ⇒ No
B) ⇒Yes, when liquid or solution
C) ⇒Yes
D) ⇒No
E) ⇒Yes
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If you've ever shifted realities, How long did it take you?
Answer:
2 days.
Explanation:
what is the name of CH3CH2CH2C(O)CH2CH3
Answer:
1-methoxypropane
Explanation:
The combination of two or more atoms, from the same or different elements, creates a(n).
a. element
c. molecule
b. atom
d. mixture
Please select the best answer from the choices provided
Pls help!!!! Fast!!!
B
С
D
Answer:
c Molecule
Explanation:
cuz science
Please helpppp!!!!!! It's 6th-grade thermal energy science.
Answer:
b?
Explanation:
The answer is C: Radiant energy from the sun travels through the glass, is absorbed by the black pot, and reflected by the aluminum foil.
What is the precise volume of the liquid
Describe the function of a cilia.
Answer:
hope it helps..
Explanation:
'Motile' (or moving) cilia are found in the lungs, respiratory tract and middle ear. ... These cilia have a rhythmic waving or beating motion. They work, for instance, to keep the airways clear of mucus and dirt, allowing us to breathe easily and without irritation.
Answer: to keep airway clear of mucus and dirt allowing us to breathe easy
Explanation:
Pleaseee helpppp this is thermal energy in 6th rade and i need it quick for a formal assesment!!!!!!
Answer:The answer is B my child
Explanation:
5) A pure substance which can be decomposed by a chemical change is a
A) mixture
B) compound
C) metal
D) nonmetal
A new element was discovered. It’s average atomic mass was found to be 245.6 amu. Isotope #1 has a mass of 243.2 amu; isotope #2 has a mass of 244.9 amu; isotope #3 has a mass of 247.2 amu. Which isotope is most likely to be the most abundant?
A
Isotope 1
B
Isotope 2
C
Isotope 3
D
They all contribute the same amount
Answer:
B. Isotope 2
Explanation:
Isotopes can be defined as the atom of an element that has the same number of protons but different number of neutrons. This ultimately implies that, the isotopes of an element have the same atomic number (number of protons) but different atomic mass (number of nucleons).
Basically, the atomic mass of any chemical element found in the periodic table is equal to the weighted average of all its isotopes. Therefore, the isotope with the closest mass to the weighted average would be the most abundant.
In this scenario, a new element was discovered with an average atomic mass of 245.6 amu.
Isotope #1 has a mass of 243.2 amu.Isotope #2 has a mass of 244.9 amu.Isotope #3 has a mass of 247.2 amu.Hence, the isotope which is most likely to be the most abundant is isotope #2 that has a mass of 244.9 amu because it is closest in mass to the relative atomic mass (weighted average) of 245.6 amu.
the gram formula mass of NH4Br is what (please provide explanation, thank you)
Answer:
97.95 g/mol
Explanation:
Step 1: Define molar masses
Molar Mass of N - 14.01 g/mol
Molar Mass of H - 1.01 g/mol
Molar Mass of Br - 79.90 g/mol
Step 2: Find amounts of molar masses
1 mol N - 14.01 g/mol
4 mol H - 4.04 g/mol
1 mol Br - 79.90 g/mol
Step 3: Find molar mass of compound
Molar Mass N + 4 Molar Mass H + 1 Molar Mass Br
14.01 g/mol + 4.04 g/mol + 79.90 g/mol
97.95 g/mol
in an experiment it was found that the total charge on an oil
drop was 5.93 X 10^-18 C How many negative charges does
the drop contain? (#51)
Answer:
37 negative charges.
Explanation:
We're being asked to determine how many negative charges a drop contains from an oil drop experiment where the total charge was 5.93x10-18 C. The drop contains 37 negative charges.
It was stated and identified that we are to attempt question #51 alone.
From the given information;
The total charge on an oil drop = 5.93 × 10⁻¹⁸ C
According to Oil drop experiment carried out by Robert Milliken in (1910);
In the oil drop laboratory experiment, It was possible for Him to substitute oil for water (because water quickly evaporate). Robert Milikan adjusted the electrical voltage among the two metal plates while the oil drop continues to drop until it stopped. When the drop was stopped, the gravitational downward force on the oil drop was equivalent to the electrical upward force on the charges thereby enabling Robert Millikan to be able to estimate the electrical charge drop.
Robert Milliken identified that the magnitude of a single negative electron charge is:
= 1.6 × 10⁻¹⁹ C
∴
If in an experiment, the total charge = 5.93 × 10⁻¹⁸ C
Then;
The number of negative charges in the oil drop can be calculated as;
[tex]\mathbf{=\dfrac{5.93 \times 10^{-18}}{1.6 \times 10^{-19}}}[/tex]
= 37.063 negative charges
Therefore, we can conclude that the numbers of negative charges contained in the total drop = 37.063.
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Find the number of moles of iron atoms obtain
from 320kg of iron (3) oxide
Answer:
320 kg of iron(III) oxide contain 4007.76 moles of iron atom.
Explanation:
Given data:
Mass of iron(III) oxide = 320 kg (320000 g)
Number of moles of iron atoms = ?
Solution:
First of all we will calculate the number of moles of iron(III) oxide.
Number of moles = mass/molar mass
Number of moles = 320000 g/ 159.69 g/mol
Number of moles = 2003.88 mol
1 mole of Fe₂O₃ contain 2 moles of iron atom.
2003.88 moles of Fe₂O₃ contain,
2003.88 ×2 = 4007.76 moles of iron atom.
How much MmHg are in 30.0 psi
Answer:
1551.45 MmHg
hope this helps :D
What can you infer is causing the cryosphere to change?
Answer:
Explanation:
The cryosphere—the portion of the Earth's surface where water is in solid form for at least one month of the year—has been shrinking in response to climate warming. ... The important outcome, however, is the change and the response the human social system (infrastructure, food, water, recreation) will have to that change.
The cryosphere the portion of the Earth's surface where water is in solid form for at least one month of the year has been shrinking in response to climate warming.
What is cryosphere ?The cryosphere includes all of the earth's frozen water, including glaciers and sea ice.
The lithosphere is the solid part of the earth made up of rocks, minerals, and other elements except the ocean. It is the part which present in the outer part of the earth which includes the brittle upper portion of the mantle and crust. The part of planet where living things can be found from the upper part of the atmosphere to the lower of the oceans and pools that are thermal and made up of the parts of earth where life present in all ecosystem is known as biosphere.
The atmosphere is the thin layer of gases that covers the outer part of the planet. It gives us the many different climates, or broad way of weather conditions around the world. The hydrosphere includes all of the water on earth from the oceans to glaciers and underground water and it can be liquid, vapour, or ice.
Therefore, the cryosphere the portion of the Earth's surface where water is in solid form for at least one month of the year has been shrinking in response to climate warming.
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30 POINTS
Why would a scientist revise a model? (choose the best answer)
Group of answer choices
to cover up evidence from a previous experiment
to show off to other scientists
to add unnecessary details to the model
in order to better explain what is happening during a phenomenon
When modeling it is important to (pick two)
Group of answer choices
show beginning, middle and end if it fits the phenomenon
only use one color
make sure there is only drawings and nothing written
use zoom in bubbles to show the unobservable
Which of the following is NOT a limitation of a model
Group of answer choices
inaccurate colors
the type of material used to create the model
a messy model
shapes that are an approximation
Answer:
First Question: in order to better explain what is happening during a phenomenon
Second Question: show beginning, middle and end if it fits the phenomenon; use zoom in bubbles to show the unobservable
Third Question: the type of material used to create the model
Explanation:
First Question: You would not revise a model to "cover up evidence," that's scientifically immoral and should not be done, and showing off to other scientists is not the point of revising something.
Second Question: You should use more than one color to differentiate different parts of the model, but don't overwhelm it with color. There should be some labels in the model, so some writing is necessary.
Third Question: Inaccurate color representation does not technically limit a model unless color scheme is important, so this could be an answer, but not likely. A messy model limits a model because it makes it hard to read. Approximating shapes is a limitation because it portrays an incorrect representation of what system the model is of. The type of material used to create the model is most likely the right answer.
Match each term with its definition.
a. The position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system.
b. A molecule that donates a proton when it encounters a proton acceptor.
c. Occurs when a reaction involving an acid and its conjugate base is combined with a second reaction involving a base and its conjugate acid.
d. It ionizes completely when dissolved in water.
e. The shift in the position of equilibrium caused by the addition of a participating ion.
f. It only partially ionizes when dissolved in water.
g. It is capable of acting as either an acid or a base depending upon the solute.
h. The act of self-ionization of a solvent to produce both a conjugate acid and a conjugate base.
i. A chemical species that bears both positive and negative charges.
1. Week electrolyte
2. Bronsted-Lowry acid
3. Neutralization
4. Amphoteric solvent
5. Zwitterion
6. Auto-protolysis
7. Strong acid
8. Le Chåtelier's principle
9. Common effect
Answer:
The position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system -Le Chåtelier's principle
A molecule that donates a proton when it encounters a proton acceptor.- Bronsted-Lowry acid
Occurs when a reaction involving an acid and its conjugate base is combined with a second reaction involving a base and its conjugate acid.- Neutralization
It ionizes completely when dissolved in water.- Strong acid
The shift in the position of equilibrium caused by the addition of a participating ion.- Common ion effect
It only partially ionizes when dissolved in water.- Weak electrolyte
It is capable of acting as either an acid or a base depending upon the solute- Amphoteric solvent
The act of self-ionization of a solvent to produce both a conjugate acid and a conjugate base.- Auto-protolysis
A chemical species that bears both positive and negative charges.- Zwitterion
Explanation:
In the answer box we have various chemical terminologies and their definitions. In answering the question, you must carefully read through each definition, then check what option best matches that definition from the options provided.
Each definition applies only to one terminology as you can see in the answer above.
Where is the north pole of the bar magnet, based on the magnetic field lines
shown?
Answer:On the Right End
Explanation: Trust me I just got it wrong on APEX to answer it for y’all On the right end is the correct answer
Answer:
Right end
Explanation:
Just did the quiz
which statement describes how technology has increased our information on Mars?
A. The Curiosity rover found sulfur compound in rocks.
B.The Curiosity rover located methane in soil samples.
C. The Curiosity rover detected carbon in organic molecules.
D. The Curiosity rover discovered helium in underground pockets.
Answer:
Either D or C. I'm so sorry if I got you the wrong answer
Answer:
c
Explanation:
Calculate the density of an
object with a mass of 20 g
and a volume of 2.3 mL.
Answer:
8.7g/mL
Explanation:
I used the density formula to solve. d=m/v= 20g/2.3mL
Answer:
8.7 g/ml
Explanation:
the formula for density is D = M/V