Pls help me I’m having a hard day pls answer these?

Answer:

mitosis and fertilization is a required answer.

Answer:

meiosis and mitosis

Explanation:

the difference is that meiosis goes through it twice.

Answer: B. 4

Explanation:

Answer:

it is he

Explanation:

beacuse Noble gases have 2 volence

Answer:

Na₂SO₄•(H₂O)₆.

Explanation:

The mass that is lost when the sample is heated is water.

Let's assume we have 100 g of the hydrate:

43 grams would be water (H₂O), while the rest (100-43=57) would be sodium sulfate anhydrous (Na₂SO₄).

We convert both those masses to moles, using their respective molar masses:

We can write those results as (Na₂SO₄)₀.₄₀•(H₂O)₂.₃₉. Now we just need to multiply those numbers so that they become integers.

If we multiply both coefficients by 5 we're left with (Na₂SO₄)₂•(H₂O)₁₂.

Simplify and thus the final answer is Na₂SO₄•(H₂O)₆.

Answer:

Covalent-network (also called atomic) solids—Made up of atoms connected by covalent bonds; the intermolecular forces are covalent bonds as well. Characterized as being very hard with very high melting points and being poor conductors. Examples of this type of solid are diamond and graphite, and the fullerenes.

I hope it's helpful!

Answer:

network solid

Explanation:

Answer:

1 ans is atmosphere

2 ans is Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions. It can have harmful effects on plants, aquatic animals, and infrastructure.

Answer:

The number of particles in the 41.8g sample of Bismuth is 12.044 × 10²³

Explanation:

In a 15.5 g sample of bismuth there are 4.47 x 10²² atoms are present.

The term molar mass is defined as the ratio between the mass and the amount of substance of any sample of said compound. The molar mass is a property of a substance.

The molar mass of a compound can be calculated by adding the standard atomic masses in g/mol of the constituent atoms.

Given:

Mass of Bismuth  = 15.5g

Number of atoms  = ?

To find the number atoms, find the number of moles in this element first.

Number of moles  = mass/ molar mass

Number of moles  =  15.5g / 209    

= 0.074mole

1 mole of a substance contains 6.023 x 10²³ atoms

0.074 mole of Bismuth will contain 0.074 x 6.023 x 10²³ atoms

= 4.47 x 10²² atoms

Thus, 4.47 x 10²² atoms are found in a 15.5 g sample of bismuth.

To learn more about the molar mass, follow the link;

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Answer:

The correct answer is - valid.

Explanation:

In this case, there is consistency in the results measures in the experiment which makes this method reliable. The consistency of a measure is referred to the reliability.

It is also given that the level of contamination of individual containers as per the average parameter of the contamination of large containers which makes this method not valid as the measurement method is how correctly it measures the true value of the parameter.

Thus, the correct answer is - method is reliable, but not valid.

Answer:

A. 15859.2 L or 15900 L

B. 0.629 mol

Explanation:

At STP, one mole is equal to approximately 22.4 L

L or mL is volume, so you are attempting to solve for L or mL.

A.

708 mol x (22.4 L/1 mol) = 15859.2 L (w/ significant figures included - 15900 L)

B.

(14.1 L) x (1 mole/ 22.4 L) = 0.629 mol.

Answer:

m = 79.1 grams

Explanation:

Given that,

Density, d = 2.26 g/mL

Volume occupies, V = 35 mL

We need to find the mass of the substance. We know that the density of an object is equal to the mass per unit volume. So,

d = m/V

[tex]m=d\times V\\\\m=2.26\ g/mL\times 35\ mL\\\\m=79.1\ g[/tex]

So, the mass of the substance is 79.1 grams.

Answer:

I guess you mean by non element example. Non element examples have more than one elements. Carbon dioxide is a non element example since caebon dioxide has 2 oxygen atoms + 1 carbon atom = carbon dioxide.

I think catalyst is also a non element example because catalyst is inorganic which means that it is not a living thing. Since catalyst is in brass and brass is a non element example, I think catalyst is also a non element example.

Hope that helps, thank you !!

Answer:

0.25 moles

Explanation:

The molar mass of NaOH is 40 g/mol.  

[tex]\frac{10g}{40g/mol}[/tex]  This equals 0.25 moles

Answer:

98.08 g/mol

Explanation:

Hope this helps.

Answer:

b. Ni, Fe, Ti, K

Explanation:

The given elements are present in period 4 of periodic table. Now we will discuss the trend of atomic radius along period.

Atomic radius:

" It is the smallest distance from nucleus to the outer most valance shell of an atom"

When we move from left to right in the periodic table the number of valance electrons in an atom increase. The atomic size goes to decrease in same period because of edition of electron with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. In this way positive charge is also going to increase and this charge is greater in effect than the charge of electrons. This effect causes the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell come closer to the nucleus.

As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.

Ni ∠ Fe ∠ Ti ∠ K

Answer:

I think is D

Explanation:

PLEASE MARK ME AS BRAINLIEST

i think the answer is 6 prairie dogs, 3 coyotes ,the grass

Hope this helps

Have a great day/night

Feel free to ask any questions

Answer:

[He]2[tex]s^{2}[/tex]3[tex]p^{1}[/tex]

Explanation:

The electron configuration for Boron is 1[tex]s^{2}[/tex]2[tex]s^{2}[/tex]3[tex]p^{1}[/tex], but you can also write it as the noble gas configuration, which is [He]2[tex]s^{2}[/tex]3[tex]p^{1}[/tex]

Note that helium has the configuration of 1[tex]s^{2}[/tex], so we instead of writing it, we write [He]. This can be useful when writing the configurations of elements from the later periods as it saves space.

Answer:

gtjgyjtjyjjjjk

Explanation:

Answer: We start by doing a 1/10 serial dilution, using 100 µL of 1M solution into 900 µL of water, until we get a 1.0x10^-5M (0.00001M) solution. Then use 1 mL of this 1.0x10^-5M solution into 9 mL of water.

Explanation:

To answer this question, we must use the law of conservation of mass, which states: In every chemical reaction mass is conserved, this means the total mass of the reactants is equal to the total mass of the products. The law implies that mass can neither be created nor destroyed, but it can be transformed. For example, in chemical reactions, the mass of the chemical components before the reaction is equal to the mass of the components after the reaction. Therefore, during any chemical reaction and low-energy thermodynamic processes in an isolated system, the total mass of the reactants or starting materials must be equal to the mass of the products. This law is quite accurate for low-energy processes, such as chemical reactions.

So, if the solution to be used is 1M , and a 10 mL of a 1.0x10^-6M solution is needed, we use the following equation:

Initial concentration x initial volume = final concentration x final volume.

The initial concentration is 1M, the final concentration is 1.0x10^-6M and the final volume required is 10 mL.

1M x initial volume = 1.0x10^-6M x 10 mL

initial volume=  1.0x10^-5 mL= 0.01 µL of 1M solution.

Since the final volume is 10 mL, we have to add the difference in volume with water, which is 10 mL - 1.0x10^-5 mL= 9.99999 mL.

However, since 0.01 mL is a very small volume that is difficult to take, the best option in this case is to make serial dilutions.

Usually, we start from a concentrated solution and prepare a series of dilutions to the tenth (1:10) or half (1:2). In this way a series of solutions is obtained, related for example by a dilution factor of 10, i.e. 1/10; 1/100; 1/1000 and so on.

Here we can prepare a series of dilutions to the tenth, from 1M to 1.0x10^-6.

We start by doing a 1/10 dilution, using 100 µL of 1M solution into 900 µL of water. This is a 0.1M solution. Then we take 100 µL of it into 900 µL of water to get a 0.01M solution. We continue doing that until we get a 1.0x10^-6M (0.000001M) solution. This final solution is the desired concentration, however we need 10 mL of it, and actually we have 1 mL. So we can just take 1 mL of the 1.0x10^-5M solution into 9 mL of water:

1.0x10^-5M x 1 mL = 1.0x10^-6M x 10 mL.

Explanation:

You have 112 g of Fe.

The atomic mass of Fe is 56 g/mol

112g Fe/ 56g/mol = 2 mol Fe  <---- you have to convert to moles of iron(iii) sulfate

From the balanced equation, you get that 2 moles of Fe react to produce 1 mole of Fe2(SO4)3

So, to convert:

2 mol Fe* (1 mol Fe2(SO4)3 / 2 mol Fe) = 1 mol Fe2(SO4)3

moles of Fe cancel and the answer is 1 mole of iron(iii) sulfate.

Answer:

Explanation:

Chromium nitrate Cr( NO₃ )₂

Chromium hydroxide Cr( OH)₃

Chromium oxide ( Cr₂O₃ )

1 mole of chromium nitrate will form 1 mole of chromium hydroxide

1 mole of chromium hydroxide will form one mole of chromium oxide .

Moles of chromium nitrate in 56 mL of .6 M solution

= .056 x .6 = .336 moles

.336 moles of chromium nitrate will produce .336 moles of chromium hydroxide and .336 moles of chromium hydroxide will produce .336 moles of chromium oxide .

So chromium oxide produced = .336 moles

Molecular weight of chromium oxide = 152

.336 moles of chromium oxide is equal to

.336 x 152 grams of chromium oxide

= 51.07 grams .

Answer:

Magma

Volcanic glass

Granite and pumice

Explanation:

Answer:

Magma,

Volcanic Glass,

Granite and Pumice,

Lava

Explanation:

Answer:

A value that quantifies the distance traveled by a substance relative to the distance traveled by the solvent- Retention factor

The substance to which the sample is bound at the start of an experiment- stationary phase

The substance that carries the components of a mixture- mobile phase

Explanation:

The retention is defined as a value that quantifies the distance traveled by a substance relative to the distance traveled by the solvent. It shows us how effective a solvent is at separating a mixture.

The stationary phase is the the substance to which the sample is bound at the start of an experiment. The solvent pick up the substance to be analyzed from this stationary phase. The different components of the mixture are found to move up the stationary phase at different speeds, causing them to eventually  separate from each other.

The mobile phase is the substance that carries the components of a mixture during chromatography.

The specific heat : c = 0.306 J/g K

Given

Heat = 35.2 J

Mass = 16 g

Temperature difference : 7.2 K =

Required

The specific heat

Solution

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

Input the value :

c = Q / m.∆T  

c = 35.2 / 16 x 7.2

c = 0.306 J/g K

Divide the number of molecules N by avogadro's constant.

Let n be the number of moles then,

[tex]n=\frac{N}{N_A}=\frac{3.3\cdot10^{24}}{6.022\cdot10^{23}}=5.48\mathrm{mol}[/tex]

Hope this helps.

Answer: Wind energy.

Explanation: Wind energy is the least harmful form of energy because unlike coal. It doesn't leave a big footprint. Although, to this date every form of energy still has a footprint, it just might not be big.