ii) Distinguish between temporary and permanent hard water?

Answer:

The amount of water

The amount of sugar and

The amount of yeast

Explanation:

A constant variable is that variable in an experiment which must be kept the same for all groups in order not to alter the results of the experiment.

In this question, the independent variable i.e. the variable being manipulated is the TYPE OF SUGAR USED while the dependent variable i.e. variable that responds to change is AMOUNT OF ENERGY. Three different types of sugar were used viz: maltose, glucose, and sucrose. To not alter the outcome of the experiment, the constants of this experiment i.e. variables that must be the same for all groups of the experiment, include the following:

- The amount of water

- The amount of sugar

- The amount of yeast used

Complete Question

4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems.

a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)

b) What is the pressure of the water column expressed in mm Hg (torr)? The density of mercury is 13.6 g/mL.

c) Calculate the pressure of the hydrogen gas above the water in the column.

d) Calculate the volume occupied by the hydrogen gas at STP.

Answer:

a)  [tex]25\textdegree C=23.8 torrs[/tex]

b) [tex]P_w=758.8[/tex]

c)  [tex]P_w=758.8=735torr[/tex]

d)  [tex]V_2=20.82mL[/tex]

Explanation:

From the question we are told that:

Metal weight [tex]M_m=0.0713g[/tex]

Volume Hydrogen [tex]V_h=23.5mL[/tex]

Displace-ment Column of water 400 mm column of water

Temperature [tex]T =258\textdegree C[/tex]

Barometric Pressure [tex]p=758.8mmHg[/tex]

Vapour Pressure of water at [tex]25^oC[/tex]

Generally from (Consult Appendix E.)

a)

Va-pour Pressure of water at

[tex]25\textdegree C=23.8 torrs[/tex]

b)

Pressure of Water column

[tex]P_w=758.8[/tex]

c) Pressure of Water column (Consult Appendix E.)

[tex]P_w=758.8=735torr[/tex]

d)

Generally the equation for ideal gas is mathematically given by

 [tex]\frac{p_1v_1}{T_1}=\frac{p_2v_2}{T_2}[/tex]

Therefore

 [tex]V_2=\frac{p_1V_1T_2}{T_1p_2}[/tex]

 [tex]V_2=\frac{735*23.5*273}{298*760}[/tex]

 [tex]V_2=20.82mL[/tex]

Answer:

26.85 grams

Explanation:

The formula for mole calculations is number of moles = given mass/gram-formula mass.

The number of moles is given to us, which is 0.125.

The gram formula mass of SnSO4 is about 214.77.

Plug in the values we have into the equation. It should look like this:

0.125 = x / 214.77

Solve for x by multiplying 214.77 and 0.125. The answer should be about 26.85 grams.

Answer:

504000 J

Explanation:

Applying,

Δq = cm(Δt)............. Equation 1

Where Δq = change in thermal energy, c = specific heat capacity of water,  m = mass of water, Δt = change in temperature.

From the question,

Given: m = 2 kg, Δt = 80-20 = 60°C

Constant; c = 4200 J/kg.°C

Substitute these values into equation 1

Δq = 2(4200)(60)

Δq = 504000 J

Hence the thermal energy is  504000 J

Answer: The number of moles of gas which are present in the sample are 1.49 mol.

Explanation:

Given: Volume = 55.3 L

Temperature = [tex]23.3^{o}C[/tex] = (23.3 + 273) K = 296.3 K

Pressure = 0.658 atm

Formula used is as follows.

PV = nRT

where,

P = pressure

V = volume

n = no. of moles

R = gas constant = 0.0821 L atm/mol K

T = temperature

Substitute the values into above formula as follows.

[tex]PV = nRT\\0.658 atm \times 55.3 L = n \times 0.0821 L atm/mol K \times 296.3 K\\n = \frac{0.658 atm \times 55.3 L}{0.0821 L atm/mol K \times 296.3 K}\\= \frac{36.3874}{24.32623}\\= 1.49 mol[/tex]

Thus, we can conclude that the number of moles of gas which are present in the sample are 1.49 mol.

Answer:b

Explanation:

I searched it

Answer:

A helium nucleus

Thre types of radiation

Alpha: Helium nucleus

Beta: Electron

Gamma: Gamma rays

Answer:

it holds reactant molecules in a good position for then to react

Answer:

D. It holds reactant molecules in a good position for them to react.

Explanation:

Got a 100 on e2020.

Answer:

2

Explanation:

Answer: The correct option is [tex]NO_2(g)[/tex]

Explanation:

A catalyst is defined as the chemical species that increases the reaction rate but does not participate in it and is left behind after the completion.

A homogeneous catalyst is one that is present in the same phase as the reactants and products.

A heterogeneous catalyst is one that is present in different phase as that of reactants and products.

For the given chemical reaction:

[tex]2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)[/tex]

As all the reactants and products are in gaseous state so, the homogeneous catalyst must also be in the gaseous state only.

Hence, the correct option is [tex]NO_2(g)[/tex]

Answer:

a

Explanation:

Answer:

Tetrahedral. Tetra- signifies four, and -hedral relates to a face of a solid; “tetrahedral” literally means “having four faces. ” This shape is found when there are four bonds all on one central atom, with no lone electron pairs. In accordance with the VSEPR theory, the bond angles between the electron bonds are 109.5o ...

There are two characteristics of molecules, one is geometry and other is shape. Shape is excluding lone pair surrounding the central element and geometry is including the lone pair. Therefore, the geometry of given molecule is tetrahedral.

VSEPR stands for valence shell electron pair repulsions. VSEPR theory is used to predict the shape and geometry of molecules on the basis of valence electrons pairs that are present around the central element of the molecule.

According to VSEPR theory, Lone pair lone pair repulsion is greater than bond pair bond pair repulsion. There are so many limitations of VSEPR theory. There is a repulsion between bond pair electrons and lone pairs present on the central element.

A molecule has four bonded atoms around a central atom. The central atom does not have any lone pairs of electrons. The geometry of such molecule is Tetrahedral. Geometry does not include lone pair on central atom.

Therefore, the geometry of given molecule is tetrahedral.

To know more about VSEPR theory, here:

https://brainly.com/question/19582124

#SPJ6

Answer:

28/23

Explanation:

28 : 23

this is written as ,

28/23

u can convert into simplest form but in this question u can't so leave it as it is.

D. 8

Hope this helps! :)

______________

Answer:

D: 8 neutrons would make it most stable

Answer: The oxygen gas has a pressure of 4 atm if my volume decreases to 1 L.

Explanation:

Given: [tex]V_{1}[/tex] = 2 L,        [tex]P_{1}[/tex] = 2 atm

[tex]V_{2}[/tex] = 1 L,          [tex]P_{2}[/tex] = ?

Formula used to calculate the new pressure is as follows.

[tex]P_{1}V_{1} = P_{2}V_{2}[/tex]

Substitute the values into above formula as follows.

[tex]P_{1}V_{1} = P_{2}V_{2}\\2 atm \times 2 L = P_{2} \times 1 L\\P_{2} = 4 atm[/tex]

Thus, we can conclude that the oxygen gas has a pressure of 4 atm if my volume decreases to 1 L.

Answer:

Thompson's experiments with cathode ray tube showed that every atom contains a small amount of negatively charged subatomic particles. Thomson proposed the plum pudding model of the atom.

Explanation:

Answer:

2.49moles

Explanation:

To calculate the number of moles (n), of iron (Fe) in 1.5 × 10²⁴ atoms, we divide the number of atoms by Avogadro's number (6.02 × 10²³).

That is, n = N ÷ nA

Where;

n = number of moles (mol)

N = number of atoms

nA = Avogadro's constant

n = 1.5 × 10²⁴ ÷ 6.02 × 10²³

n = 1.5/6.02 × 10(²⁴ - ²³)

n = 0.249 × 10¹

n = 2.49moles

Answer:

the valency of sodium is one because sodium loses 1 electron to become stable

Answer:

when d volume of a substance is high, the concentration is gonna b low...

Jus lyk putting much water in just a cube of sugar

Explanation:

So lower volume, higher concentration

Answer:

Organic molecules are important to living things because life is based on the properties of carbon.

Properties of Carbon

Carbon is an important element because it can form four covalent bonds.

Carbon skeletons can vary in length, branching, and ring structure.

The carbon skeletons contain the functional groups that are involved in biochemical

Explanation:

Hope it helps

omg yees

eExplanation:

Answer:

The entropy and the systems surrounding it tend to increase.

Answer: The entropy in a system and its surroundings tends to increase.

Explanation:

3.3.2 Quiz: Entropy (a p e x)

Answer:

16.7 %(m/m)

Explanation:

The percent by mass of a solution (% m/m) is defined as 100 times the ratio of the mass of solute (The substance in the lower amount, NaCl) and the mass of the solution = Mass solute + Mass Solvent (water).

Mass Solution:

100g NaCl + 500g water = 600g solution

Mass Percent:

100g NaCl / 600g solution * 100

= 16.7 %(m/m)

Explanation:

Dinitrogen monoxide: covalent bond

copper(||) hydroxide: ionic bond

Butane: Covalent Bond

Answer

Disulfur decafluoride S2F10 covalent

calcium sulfide  CaSO3 ionic

Diphosphorus tetraiodide P2I4 ionic

dinitrogen monoxide  N2O   ionic

Aluminum chloride  AlCl3  covalent

copper(II) hydroxide  Cu(OH)2  ionic

barium sulfate BaSO4  covalent

butane  C4H10  covalent

Explanation:

edmentum

83.3% yield

Explanation:

First, we need to convert 240 g of [tex]Fe_{2}O_{3}[/tex] into moles:

[tex]240 \:g \:Fe_{2}O_{3} \:\times(\frac{1\:\text{mol}\:Fe_{2}O_{3}}{159.69\: \text {g}\:Fe_{2}O_{3}})[/tex]

[tex]=1.50 \:\text{mol}\:Fe_{2}O_{3}[/tex]

Next, find the theoretical Fe yield using molar ratios.

[tex]1.50 \: \text {mol} \: Fe_{2}O_{3}\: \times (\frac{2\: \text{mol} \: Fe}{1 \:\text{mol} \: Fe_{2}O_{3}})[/tex]

[tex] = 3.00 \: \text{mol} \: Fe[/tex]

Then convert this back into grams:

[tex]3.00 \: \text{mol} \:Fe \times (\frac{55.845 \: \text{g} \: Fe}{1 \: \text{mol} \: Fe}) = 168 \: \text{g} \: Fe[/tex]

Note that actual yield is only 140 g Fe so percentage yield is

[tex]\dfrac{140\:\text{g}\:Fe}{168\:\text{g}\:Fe} \times 100[/tex]%= 83.3%

83.3%

The answer is 83.3%