pls i have a chemistry test answers asap :'( ​

Answer:

B as all the forces cancel out

Explanation:

20-20=0

25-25=0

Answer:

golgi apparatus

Explanation:

Answer:

vacuole

Explanation:

the answer is vacuole im pretty sure!

Explanation:

protons and neutrons.....

...

Answer:

The subatomic particles are Protons and Neutrons.

Answer:

Gas

Explanation:

I dunno but a lucky guess i guess

Answer:

B. The bonds are polar and the molecule is nonpolar.

Explanation:

Each bond in the molecule is polar, as indicated by the partial charges on the atoms of the molecule. However, the four atoms are arranged symmetrically around the central atom. In this case, the effects of the partial charges on opposite sides cancel out. As a result, the molecule as a whole is nonpolar. If exposed to an electric field, the molecule will not orient itself in any particular direction.

Answer:

The third one!

Explanation:

The balanced equation for the reaction between NaOH and H2SO4 is given as;

2NaOH + H2SO4 → Na2SO4 + 2H2O  

2 mol of NaOH reacts with 1 mol of H2SO4

5g of NaOH was dissolved in 1000cm3.

Mass = 5 g

Molar mass = 40 g/mol

Volume = 1000 cm3 = 1 L

Number of moles = Mass / Molar mass

Number of moles = 5 / 40 = 0.125 mol

Molarity = Number of moles / Volume

Molarity = 0.125 / 1 = 0.125 M

25cm3 of this solution neutralized 28.3cm3 of solution containing 7.2gdm-3 of impure H2SO4.

CaVa / CbVb = Na / Nb ; where a = acid and b = base

Va = 28.3cm3

Vb = 25cm3

Ca = ?

Cb = 0.125 M

Na = 1

Nb = 2

I. The molarity of H2SO4

Solving for Ca;

Ca = CbVb * Na / (Va * Nb)

Cb = (0.125 * 25 * 1 ) / ( 28.3 * 2)

Cb = 0.0552 M

II. The concentration of the pure acid on gdm-3

Molarity = Mass conc / Molar mass

Mass Conc = Molarity * Molar mass

Mass Conc = 0.0552 * 98.079

Mass Conc = 5.41 g/dm3

III. % impurity of the acid

Percentage Impurity = Mass of pure / Mass of Impure   *  100

Percentage Impurity = 5..41 / 7.2 * 100

Percentage Impurity = 75.14%

Answer:

Dividing the mass of the water lost by the original mass of hydrate used is equal to the fraction of water in the compound. Multiplying this fraction by 100 gives the percent water in the hydrate.

Explanation:

The amount of water throughout the compound has been determined by dividing the mass of water wasted mostly by original quantity of hydrate used. The above fraction can be multiplied by 100 to get the hydrate's water content in percentages.

The proportion of matter that makes up an object is quantified by its mass. The kilogram, or kg, would be the fundamental SI unit of mass.

Any substance that contains water through the form of H2O molecules is referred to as a hydrate. This water content by weight can vary, but it is typically fixed. The most well-known hydrates seem to be crystalline solids which decompose once the attached water is removed.

Therefore , The amount of water throughout the compound has been determined by dividing the mass of water wasted mostly by original quantity of hydrate used. The above fraction can be multiplied by 100 to get the hydrate's water content in percentages.

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Answer:

Find the limiting reagent by calculating and comparing the amount of product each reactant will produce. Balance the chemical equation for the chemical reaction. The reactant that produces a lesser amount of product is the limiting reagent. The reactant that produces a larger amount of product is the excess reagent.

Explanation:

Answer:

239.7mL

Explanation:

Using the general gas equation;

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas constant (0.0821 Latm/molK)

T = temperature (K)

The balanced chemical equation in this question is as follows:

CaC2(s) + 2H2O(l) --> Ca(OH)2(aq) + C2H2(g)

From the equation, 1 mole of CaC2 produces 1 mole of ethylene gas, C2H2.

Using mole = mass/molar mass

Molar mass of CaC2 = 40 + 12(2)

= 40 + 24

= 64g/mol

mole = 0.5487/64

mole = 0.00857mol of CaC2

Hence, 0.00857mol of CaC2 produced 0.00857mol of C2H2

Based on the information provided, n = 0.00857mol, T = 43°C = 43 + 273 = 316K, p = 0.926 atm

PV = nRT

V = nRT/P

V = 0.00857 × 0.0821 × 316/0.926

V = 0.222/0.926

V = 0.2397L

In mL, volume = 0.2397 × 1000

= 239.7mL

Answer:

There are three methods used to produce salt: solar, evaporation and rock mining.

Explanation:

Explanation:

Crystallography. an arrangement in space of isolated points (lattice points ) in a regular pattern, showing the positions of atoms, molecules, or ions in the structure of a crystal.

If an atom experiences sufficient thermal activation, it can move to a neighboring lattice position.4 If the vibration frequency of the atom is v and the atom has Z nearest neighbors, the total number of jump attempts is vZ. However, only a small fraction of the attempts will be successful, with a probability depending on the ratio between the necessary activation energy for a single jump QD and the thermal activation kBT. The effective jump frequency ΓD is then

(5.6)

With each successful jump, the atom travels one atomic distance λ and the total traveling distance in unit time is thus ΓDλ. Substituting the jump frequency ΓD into the expression for the root mean square displacement of a random walker [equation (5.5)] and using the spatial coordinate r leads to

Answer:

For these problems, we need to compare the theoretical yield that we'd get from performing stoichiometry to the actual yield stated in the problem. % yield is the actual yield/theoretical yield x 100%  

Cu + 2 AgNO₠→ Cu(NOâ‚)â‚‚ + 2 Ag ==> each mole of copper yields two moles of silver  

12.7-g Cu x ( 1 mol Cu /63.5-g Cu) x ( 2 mol Ag / 1 mol Cu) x (108-g Ag / 1 mol Ag) = 43.2-g Ag. This is the theoretical yield. Now, since we got 38.1-g Ag our % yield is:  

38.1-g/43.2-g x 100% = 88.2%

Explanation:

Answer:

Explanation:

0.25 M

The molarity of a solution will be 4.27M .

Molarity (M), often known as molar concentration, is the concentration of a solution expressed in moles of solute per liter of solution.

Solution can be considered as a mixture of more than one component. It may be homogeneous solution as well as heterogeneous solution.

Gram to mole conversion:

[tex]=\;2.75\;g.\;\frac{1\;mol}{58.44g} \\=\;0.0470 \;mol[/tex]

Molarity of the solution can be calculated by using the following formula:

It is calculated that, moles of solute = 0.0470 mol, volume of the solution = 1100 mL.

Now, put the value of given data in molarity formula:

[tex]Molarity=\frac{Moles\;of\;the\;solute}{Volume \;of\; the\; solution} \\=\frac{0.0470\;mol}{1100 \;mL} \\=\;4.27\;mol/mL\\=\;4.27\; M[/tex]

Therefore,  the molarity of a solution will be 4.27M.

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Answer:

Reaction CoCl2 + 2 NaOH -> Co(OH)2 + 2 NaOH

You need to count number of moles of NaOH

Amount of mole is n = m/M = 114 g / 39.998 g/mol = 28,5 mol (about)

Amount of CoCl2 is half from that

Calculate molar mass of CoCl2 and multiply it by 28,5 mol

Explanation:

Ohm's Law states that for a linear circuit the current flowing through it is proportional to the potential difference across it so the greater the potential difference across any two points the bigger will be the current flowing through it.

(I'm happy)

Answer:

26.78 kJ

Explanation:

To solve the problem, we have to first write the stoichiometric coefficients in the chemical equation:

2P + 3Cl₂ → 2PCl₃

With these coefficients, we have the same number of atoms of each chemical element on both sides: 2 atoms of P, 6 atoms of Cl.

According to the equation, 2 moles of phosphorous (P) react with 3 moles of chlorine (Cl₂), and 574 kJ of energy are released. We have to figure out which is the limiting reactant. For this, we convert the mass into moles by using the molar mass(MM):

MM(P) = 30.9 g/mol

67.04 g P/(30.9 g/mol) = 2.17 mol P

MM(Cl₂) = 35.4 g/mol x 2 = 70.8 g/mol

10.20 g Cl₂/(70.8 g/mol) = 0.14 mol Cl₂

Now, we multiply the actual moles of P (the amount we have for the reaction) by the stoichiometric ratio given by the chemical equation (3 mol Cl₂/2 mol P):

2.17 mol P x (3 mol Cl₂/2 mol P) = 3.25 mol Cl₂

To completely react 67.04 g P, we need 3.25 mol of Cl₂, and we have only 0.14 moles of Cl₂, so the limiting reactant is Cl₂.

Now, we use the limiting reactant to calculate the energy released from the reaction. The energy released per mole of Cl₂ is:

ΔH/(3 mol Cl₂) = -574 kJ/3 mol Cl₂= 191.3 kJ/mol Cl₂

Finally, we multiply the energy released per mole of Cl₂ by the number of moles of Cl₂ we have:

0.14 mol Cl₂ x 191.3 kJ/mol Cl₂ = 26.78 kJ

Answer:

copper

Explanation:

metallic bonds occur among the metal atoms where iconic bonds join metal and nonmetals metallic bonding joins a bolt of metal atoms a sheet of aluminum foil and a copper wire are both place where you can see metallic bonding in action the Sea of electrons that is free to flow about the crystal of positive metal ions

Metallic bonding occurs between metal atoms. Among the given copper is example of metal in which copper atoms are strongly held by metallic bonds.

Metals are electropositive elements. Metals contains a pool of mobile electrons among the sea of positive ions. Metals exhibit some peculiar features such as conductivity, hardness, malleability, ductility, luster etc.

Metals atoms form well orders crystalline structure in which particles are held together by strong metallic bonds. In periodic table, the first two groups and all the d-block elements are metals.

Copper is a transition metal in d-block. Copper is a very important metal in our lives and in industries since it is used in constructions, electronics, house hold items etc., because of its hardness and conductivity. Hence, option 2 is correct.

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Answer:

N2 + 3H2 → 2NH3. 14 moles a. If 6 mol of H2 are consumed, how many moles of NH3 are produced? ... a 3 mol H₂. 4. How many moles of nitrogen are needed to make 11 moles of NH3? Il mol NH₃ x Imol Na = 15.5

Answer:

[tex]V_{base}=43.5cm^3[/tex]

Explanation:

Hello there!

In this case, given the neutralization chemical reaction of barium sulfate and nitric acid, it is possible to evidence the 1:2 mole ratio between them; thus, at the equivalence point we have:

[tex]2n_{base}=n_{acid}[/tex]

Which in terms of molarities and volumes is:

[tex]2M_{base}V_{base}=M_{acid}V_{acid}[/tex]

In such a way, by solving for the volume of base, we proceed as follows:

[tex]V_{base}=\frac{M_{acid}V_{acid}}{2M_{base}} \\\\V_{base}=\frac{45cm^3*0.29mol*dm^{-3}}{2*0.15mol*dm^{-3}} \\\\V_{base}=43.5cm^3[/tex]

Best regards!

Answer:

yes you do so you know how strong it is how maluble it's is so it can be customised to it's specific use

Answer:

alloy's properties are usually different from those of its component elements. Alloy constituents are usually measured by mass. Unlike pure metals, most alloys do not have a single melting point; rather, they have a melting range in which the substance is a mixture of solid and liquid.

Alloy steels have a wide range of special properties, such as hardness, toughness, corrosion resistance, magnetizability, and ductility. Nonferrous alloys, mainly copper–nickel, bronze, and aluminum alloys, are much used in coinage.

Pure metals are useful but their applications are often limited to each individual metal's properties. Alloys allow metal mixtures that have increased resistance to oxidation, increased strength, conductivity, and melting point; Essentially any property can be manipulated by adjusting alloy concentrations.

dnt learn all thr properties.

these are the main properties..u can learn thse only. hope it will help u

Answer:

coal chemicals sun

Explanation:

0.16

Explanation:

when you divided 1.2.00 with 740 you get this number.

Answer:

It's important for scientists to know the properties of matter because all things are made up of matter. Each type of matter has different physical characteristics and scientists need to know and understand these characteristics to make calculations. ... The main phases of matter are solid, liquid, and gas.