The material the start all reactions are ______ and the materials that are formed are called _____.

Answer:

4,25% v/v H3PO4

Explanation:

The concentration of phosphoric acid (H3PO4) is expressed as a volume / volume percentage, which means:

%v/v H3PO4 = (mL of pure H3PO4/mL of solution)*100%

In other words, we are only interested in the final volume of the solution to which the phosphoric acid was diluted, regardless of its composition. Which in this case is 1 L (1000 mL).

We can then apply the following equation, commonly used to calculate the initial or final concentration (or volume) of a substance when it is diluted:

Ci*Vi=Cf*Vf

Where:

Ci, is the initial concentration of the substance.

Vi, the initial volume of the substance

Cf, the final concentration reached after dilution

Vf, the final volume of the solution at which the substance was diluted

In this case, the incognite would be the final concentration of H3PO4 reached after dilution, that is, Cf. Therefore, we proceed to clear Cf from the previous equation and replace our data:

Cf = (Ci*Vi)/Vf = (85% v/v * 50 mL)/1000 mL = 4,25 % v/v

Note that being up and down in the division, the mL unit is canceled to result in% v / v.

Answer: False

Explanation: Alloys are harder and stronger because the different-sized atoms of the mixed metals make the atomic layers less regular, so they cannot slide as easily.

Answer:

0.623 moles of H₂O.

Explanation:

• balanced equation: 2C₂H₆ + 7O₂ -> 4CO₂+ 6H₂O

Given:

• 6.23g of C₂H₆

• C₂H₆ molar mass is 30

solve for moles of C₂H₆

• moles = mass/mr

• moles = 6.23/30

• moles = 0.2077

solve for moles of H₂O using molar ratio

• 2C₂H₆ : 6H₂O

• 2 : 6

• 0.2077 : 0.623

Therefore, found that 0.623 moles of H₂O is produced.

Answer:

There are currently a variety of advanced medical treatment screening programs for certain types of cancer that have resulted in more people having a better chance of healing or living longer.

Explanation:

Exercise helps cancer survivors cope with and recover from treatment; exercise may improve the health of long term cancer survivors and extend survival. Physical exercise will benefit throughout the spectrum of cancer. However, an understanding of the amount, type and intensity of exercise needed has not been fully elucidated. There is sufficient evidence to promote exercise in cancer survivors following careful assessment and tailoring on exercise prescription.

"The field  of  oncology will benefit  from understanding the importance of  physical activity both for primary prevention as well as in helping cancer survivors cope with and recover from treatments, improve the health of long term cancer survivors and possibly even reduce the risk of  recurrence and extend survival after a cancer diagnosis" (P. Rajarajeswaran,  R. Vishnupriya)

Additional studies will be needed to more firmly establish physical activity benefits to cancer survivors.

• R. Segal, MD*, C. Zwaal, MSc†, E. Green, RN‡, J.R. Tomasone, PhD§, A. Loblaw, MD MSc‖, T. Petrella, MD, Exercise for people with cancer: a clinical practice guideline. 2017. Canadian Cancer Research Journal.

• A systematic review and meta-analysis of the safety, feasibility and effect of exercise in women with stage II+ breast cancer. Archives of Physical Medicine and Rehabilitation, May 2018.
• Efficacy of exercise interventions in patients with advanced cancer: A systematic review. Archives of Physical Medicine and Rehabilitation, May 2018.

• McNeely ML. Exercise as a promising intervention in head & neck cancer patients. Indian J Med Res.
• P. Rajarajeswaran,  R. Vishnupriya. Exercise in cancer. College of Physiotherapy, Mother Theresa Post Graduate and Research Institute of Health Sciences, India.

Exercise is key both in the prevention and treatment of cancer, since it improves the quality and life expectancy of patients.

How would you market your services to clients that have cancer?

The benefits of exercise against cancer are innumerable: it helps prevent it, reduces the side effects of chemotherapy and radiotherapy, decreases cancer recurrence, improves vital energy, mobility and balance and reduces fatigue, maintains muscle mass, improves self-esteem and sleep quality, decreases the level of anxiety, depression and stress.

No one doubts the importance of physical activity, exercise and sport in global health, in the prevention and even in the treatment of numerous diseases. Among these diseases is cancer. There are more than 10,000 scientific publications that have studied the links between exercise and cancer and almost all of them with positive results regarding the prevention of numerous types of tumors, the decrease in cancer recurrence and the best prognosis of the latter if You exercise.

It is scientifically proven that properly prescribed physical exercise can be performed without risk during and after chemotherapy and radiotherapy treatments. However, it is necessary to adjust its intensity, duration, weekly frequency and type of exercise to the general condition of the patient. Physical exercise will improve the quality of life, fatigue and mood of the cancer patient being treated. It will also improve the prognosis of the disease, its quality of future life and its final life expectancy.

Research the benefits and risks of exercise and youth.

The benefits of physical activity and sports in young people imply a better physical condition, but also plays a fundamental role from the psychological and social. Every healthy habit is best incorporated from childhood, so that it becomes natural and everyday and improves the quality of life of our future adults.

The benefits of physical activity in youth are several:

• Better cardiorespiratory function and greater muscular strength

• Fat reduction, children and young people who perform physical activity have lower body fat.
• Decreased risk of subsequent cardiovascular and metabolic diseases such as high blood pressure, diabetes, high cholesterol.
• Better bone health, because the growing bones are strengthened.
• Fewer symptoms of depression since they do not get bored, find motivations and social relationships.

Children and young people should perform daily physical activities in the form of commuting, games, recreational activities, physical education, programmed exercises and sports, in the context of school and clubs, if possible integrating other family members.

The reactions that would have the smallest value of K is

A + B → 2 C; E°cell = -0.030 V

Option A

Generally the equation for the number of electrons transferred  is mathematically given as

where

T= Temperature

F=25C(298K)

R = Gas constant

R= 8.314 J/K.mol

F = Faraday's constant

F= 96500 C

We see from the equation that the E-cell is directly proportional to K(equilibrium constant of the reaction)

Hence, The reactions that would have the smallest value of K is

A + B → 2 C; E°cell = -0.030 V

For more information on Reaction

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Answer:

The reaction with smallest value of K is :

A + B → 2 C; E°cell = -0.030 V

Explanation:

where :

n = number of electrons transferred

F = Faraday's constant = 96500 C

= standard electrode potential of the cell

R = Gas constant = 8.314 J/K.mol

T = temperature of the reaction =

= equilibrium constant of the reaction

As we cans see, that standard electrode potential of the cell is directly linked to the equilibrium constant of the reaction.

• Higher higher will be the value of K.
• Lower lower will be the value of K.

So, the reaction with smallest value of electrode potential will have smallest value of equilibrium constant. And that reaction is:

A + B → 2 C;

We are given:

Maximum concentration of Lead in water = 9 ppb

Mass of Lead in the given solution = 20 grams

Volume of water in the given solution = 250 mL

What is 1 ppb?

1 ppb, short for parts-per-billion. As from its name itself, ppb is used to find how many molecules of solute are present per 1 Billion molecules of the solvent

you can also use it in grams to get the formula:

1 ppb = 1 gram of solute / 1 Billion grams of Solvent

Finding the Ideal ppb concentration:

We are given that the maximum allowed concentration is 9 ppb

which means that we need 9 grams of the solute per 1 Billion grams of Solvent:  9 grams of Solute / 10⁹ grams of Solvent

ppb Concentration of the given solution:

We have 20 grams of Solute in 250 mL of water

Since the density of water is 1 gram/mL

20 grams of Solute / 250 grams of Solvent

As we can see, this fraction is FAR more large that the maximum ppb concentration

This means that the concentration of Lead in the Given solution is higher than the maximum amount and Hence, is unfit to drink