pls help 8th grade k12

Answer:

Explanation:

I hope this helps

Explanation:

Mole ratio of NaOH : HCl = 1: 1

Moles of NaOH used = 0.1 mol/1000 cm3 × 27.20 cm3

= 2.72 × 10^-3 mol

Therefore moles of HCl used is also 2.72 × 10^-3 mol

So concentration of HCl can be found by dividing the no.of moles of HCl by the volume of HCl as follows

2.72 × 10^-3 mol/ 5cm3

1000cm3 = 1dm3

Therefore,

1cm3 = 1/1000 dm3

5cm3 = 5/1000 dm3

HCl conc. = 2.72 × 10^-3 mol/ 5×10^-3 dm3

= 0.544 moldm-3

Answer:

You are not showing the question, but I believe the answer is cis-3,4-dimethyl-3-hexene.

Explanation:

since the substituents are on same side, it call cis. Followed by the name.

Answer:

The element X is sulfur.

Sulfur will gain 2 electrons to become an ion.

The charge of sulfide ion is (2-).

Explanation:

Answer:

Explanation:

It''s chemical formula is Na3PO4

The pH of the standard hydrogen electrode that has electrode potential of -0.128 V  is 4.3.

The equation of the hydrogen electrode is;

2H^+(aq) + 2e ⇄ H2(g)

The standard electrode potential of hydrogen is 0.00 V

Using the Nernst equation;

Ecell = E°cell - 0.0592/n log Q

Now;

E°cell = 0.00 V

n = 2

Q = 1/[H^+]

-0.128 = 0.00 - 0.0592/2 log  1/[H^+]

-0.128 = 0.00 - 0.0296 log 1/[H^+]

 -0.128 =  - 0.0296 log 1/[H^+]

-0.128/  - 0.0296  =  log 1/[H^+]

1/[H^+] = Antilog (4.32)

[H^+] = 4.79 × 10^-5

Now;

pH = -log[H^+]

pH = -log (4.79 × 10^-5)

pH = 4.3

Learn more: https://brainly.com/question/11155928

Answer:

Answer is 2

Explanation:

directly pro

Considering the Boyle's law, the volume of the balloon at the higher altitude is 7.5 L.

The gas laws are a set of chemical and physical laws that allow determining the behavior of gases in a closed system. The parameters evaluated in these laws are pressure, volume, temperature and moles.

Boyle's law is one of the gas laws that states that the pressure of a gas in a closed container is inversely proportional to the volume of the container, when the temperature is constant. In other words, if the pressure increases, the volume decreases; while if the pressure decreases, the volume increases.

Boyle's law is expressed mathematically as:

P× V = k

In this law then two variables are related: pressure and volume, so it is assumed that the temperature of the gas and the number of molecules of the gas are constant.

Studying an initial state 1 and a final state 2 is fulfilled:

P1× V1= P2× V2

In this case, you know:

Replacing:

1 atm× 6 L= 0.80 atm× V2

Solving:

[tex]V2=\frac{1 atm x 6 L}{0.80 atm}[/tex]

V2= 7.5 L

Finally, the volume of the balloon at the higher altitude is 7.5 L.

Learn more:

Answer:

Forged parts are often tougher than cast parts. This can be determined by performing tensile tests on various areas on the parts. Additionally, the microstructures of forged and cast parts can be used to determine if a part was forged or cast. The microstructure of a cast part will have a more uniform grain structure.

Explanation:

Answer:

Explanation:

You have to find the mass in the mole before the molarity and then in the mole.

Answer: C

Explanation: trust me bro

Increase in temperature does not change the rate of collisions between particles in a reaction.

The collision hypothesis offers suggestions for how to alter the rate of a reaction as well as an explanation for why certain reactions occur at various rates.

According to the collision theory, for a chemical reaction to take place, the reacting particles must come into contact with one another. The frequency of collisions affects the reaction's rate. According to the idea, responding particles frequently encounter without reacting.

Any analysis of an ordinary reaction mechanism must start with this rule. It explains why there are so few termolecular reactions. According to the kinetic theory of gases, there will only be one instance in which three molecules collide at once out of every 1000 binary collisions.

Therefore,  Increase in temperature does not change the rate of collisions between particles in a reaction.

To learn more about Temperature, refer to the link:

https://brainly.com/question/20162899

#SPJ2

Answer:

1. An independent variable is manipulated, or changed. The dependent, or responding variable, changes based on the independent variable. The dependent variable is examined.

2. It is a controlled experiment.

Explanation:

In a controlled experiment all variables are kept the same, except for the one being tested, which is called the experimental variable , or independent variable . This group is the experimental group . The group that is not affected by the experimental variable is the control group .

Very often a graph will be used to analyze the results of the experiment. The independent/experimental variable is placed on the x-axis and the dependent variable is placed on the y-axis. The dependent variable is what is measured as a result of the application of the experimental variable.

A variable that is independent is altered. Based on the independent variable, the responding variable, or dependent variable, alters. Examining the dependent variable. The experiment is carefully controlled.

In mathematical modeling, statistical modeling, and experimental sciences, there are dependent and independent variables. Dependent variables get their name because, during an experiment, their values are investigated under the presumption or requirement that they are dependent on the values of other variables due to some law or rule.

A variable that is independent is precisely what it sounds like. It is a stand-alone variable that is unaffected by the other variables you are attempting to assess. Age, for instance, could be an independent variable.

When doing an experiment, the independent variable is what you alter, and the dependent variable is what changes as a result of that change. This is an easy way to conceive of independent and dependent variables.

Thus, based on the independent variable, the responding variable, or dependent variable, alters.

To learn more about independent variable, follow the link;

https://brainly.com/question/967776

#SPJ2

Answer:

e

Explanation:

Answer:

Explanation:

The required pressure can be found by using the formula for Boyle's law which is

[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

From the question we have

[tex]P_2 = \frac{1 \times 196}{26} = \frac{196}{26} \\ = 7.538461...[/tex]

We have the final answer as

Hope this helps you

Answer:

Cell are the smallest life units on this planet

Explanation:

Answer:

a. Constant shape

The freezing point of a solution prepared by dissolving biphenyl (C12H10) into naphthalene is  67.99oC.

Freezing point can be obtained from;

ΔT = K m i

ΔT = freezing point depression

m = molality of the solution = 1.506 m

i = Van't Hoff factor = 1 for molecular substances

K = Freezing constant of naphthalene = 8.15 oC/m

ΔT = 8.15 oC/m × 1.506 m × 1 = 12.27oC

Freezing point of pure naphthalene = 80.26 °C

ΔT =  Freezing point of pure naphthalene - Freezing point of solution

Freezing point of solution =  Freezing point of pure naphthalene - ΔT

Freezing point of solution =  80.26 °C - 12.27oC = 67.99oC

Learn more:

Answer:

The mass of objects remains constant throughout the universe. This is because an object is made of he same amount of matter (atoms), no matter where you take it in the universe. If you take an object from the Earth to the moon, only the weight will change.

Explanation:

My classmate's statement in incorrect because plants are also composed of cells.

All living things are composed of cells. A cell is the smallest unit of living organisms. Cells obtain energy via the process of cellular respiration. During cellular respiration, glucose is broken down to yield carbon dioxide and water.

In photosynthesis, carbon dioxide and water are combined to form glucose. The two processes are opposites of each other. Plants produce their own food via photosynthesis. Since plants are composed of cells, plant cells also undergo cellular respiration therefore my classmate's statement in incorrect.

Learn more: https://brainly.com/question/11324711

Air resistance opposes the gravity in a falling object hence the object loses speed once it reaches terminal velocity.

According to the experiment of Galileo, in the absence of air resistance, all objects that are thrown down from the same height will hit the ground at he same time due to the effect of gravity.

We know that the air resistance makes the acceleration of object to become less than the acceleration due to gravity. So, air resistance opposes the force of gravity and causes falling objects to lose speed once they reach terminal velocity.

Learn more: https://brainly.com/question/865531

Answer:

The answer is D - Air resistance opposes the force of gravity and causes falling objects to lose speed once they reach terminal velocity.

Ill explain why -, for example ,

When the paper is smooth, it exposes a large surface to the air beneath it which slows its descent. Once it is crumpled, the surface which comes in contact with the air is much smaller, allowing it to fall much faster.  At first, you probably thought the book would touch the ground first since it is heavier However, once the piece of paper was crumpled, they hit the ground at the same time! Funny, since it is the same piece of paper and the book is still heavier. It all comes down to form. I hope this helped u with the test !!

AnswerExplanation:I finsished d

Answer:

17.55L

Explanation:

0.48mol : 11.7

0.72mol :   x

0.48x = 8.424

x = 17.55

Answer:

NaHCO3

Explanation:

The three is small at the bottom at the end

Rutherford proposed the nuclear model of atom. The only one model which can be inferred from this model is nucleus with protons and revolving electrons around.

Rutherford proposed some aspects of atomic structure based on his gold foil experiment. He discovered that the alpha ray is scattering from foil by the repulsion it experienced from the metal.

This results lead to the discovery of positively charged particles in atom latter called as protons. Rutherford proposed that theses protons are located inside the nucleus and the electrons are revolving around the nucleus.

Latter Niels Bohr his student interpreted the nuclear model of Rutherford with quantum mechanics and theory of max planck and he proposed the equations for the determination of energy and momentum of electrons and the radius of atom.

Therefore, no other inferences except the presence of protons and revolving electrons can be obtained from Rutherford's model of atom.

To find more about nuclear model, refer the link below:

https://brainly.com/question/18521318

#SPJ2

Answer:

I would say D and A

But i might be wrong

Answer:

A and D

Explanation:

Now try marking the other guy as brainiest.

Answer:

The answer is A and C.

Explanation:

The reactants in the process of cellular respiration are oxygen and glucose, respectively. It is ATP that serves as the primary product of cellular respiration, with carbon dioxide and water serving as waste products.

Sugar is a glucose.

Oxygen and glucose are the two  substances that are reactants in the chemical reactions of cellular respiration. Therefore, the correct options are options A, C.

Through the process of cellular respiration, organisms mix oxygen with food molecules, directing the chemical energy contained in these substances towards life-sustaining processes while excreting carbon dioxide and water as waste. Foods are broken down by microorganisms that do not require oxygen in a process known as fermentation.

Adenosine triphosphate (ATP), an energy-rich compound that absorbs the chemical energy generated by the decomposition of food molecules then releases it to power other cellular functions, is one goal of the breakdown of foodstuffs. ATP is created when the energy found inside chemical bonds is converted from one form to another. Oxygen and glucose are the two  substances that are reactants in the chemical reactions of cellular respiration.

Therefore, the correct options are options A, C.

To know more about cellular respiration, here:

https://brainly.com/question/29760658

#SPJ2

Answer:1. Decission

2.Structured or programmed decision

3.Unstructured or non -programmed decisions

4.Forecasting

5.Contingency planning

6.Scenario planning

7.Bench marking

8.Participatory planning

9.quantitative

10.qualitative

11.Uncertainty conditions

12.eigt steps

13. Decision making

14.Trigger point

15.Certainty conditions

Explanation:

It's all about organization and management.

Explanation:

I hope it helps