pLeeease help im so tired and i need to SLEEP. Answer the 1s you know
1. How does the mechanical energy of a ball that is starting to fall compare to its total energy just before it hits the floor?
2. When you stand in sunlight, what form of energy is emitted by the sun?
3. An eye doctor wants to design reading glasses that also function as sunglasses. Should the eye doctor use a reflective-transparent material or a reflective-opaque material for the lenses? Support your claim.

Answer:

reproduction and life are connected because when you reproduce you are creating life.

The pH = 2.41

Given

5.0% by mass solution of acetic acid

the density of white  vinegar is 1.007 g/cm3

Required

pH

Solution

Molarity of solution :

[tex]\tt M=\dfrac{\%mass\times \rho\times 10}{MW~acetic~acid}\\\\M=\dfrac{5\times 1.007\times 10}{60}\\\\M=0.839[/tex]

Ka for acetic acid = 1.8 x 10⁻⁵

[H⁺] for weak acid :

[tex]\tt [H^+]=\sqrt{Ka.M}[/tex]

Input the value :

[tex]\tt [H^+]=\sqrt{1.8\times 10^{-5}\times 0.839}\\\\(H^+]=0.00388=3.88\times 10^{-3}\\\\pH=3-log~3.88=2.41[/tex]

White vinegar is a 5.0% by mass solution of acetic acid in water and if the density of white vinegar is 1.007 g/cm³ then the pH of solution is 4.8.

pH of any solution will be calculated as:

pH = - log[H⁺], where

[H⁺] = concentration of H⁺ ions

In this question we will calculate the concentration of H⁺ ions as:

[H⁺] = √Ka.M, where

Ka = acid dissociation constant for acetic acid = 1.8 x 10⁻⁵ (known)

M is molarity and this can be calculated as:

M = (% mass × density × 10) / Molar mass of acid

Given that,

% mass = 5.0% by mass solution of acetic acid

density = 1.007 g/cm³

Molar mass of acetic acid = 60

Now putting all these values on the above equation, we get

M = (5 × 1.007 × 10) / 60 = 0.839

Now, we calculate the concentration of H⁺ ions by putting values on that equation as:

[H⁺] = √(1.8 x 10⁻⁵)(0.839)

[H⁺] = 1.5 x 10⁻⁵

So, pH of the solution will be calculated as:

pH = -log(1.5 x 10⁻⁵)

pH = -(-4.8)

pH = 4.8

Hence, pH is 4.8.

To know more about pH, visit the below link:

https://brainly.com/question/10313314

Explanation:

Galileo found Venus went through the entire phase cycle, proving that she revolved completely around the Sun, as predicted by Copernicus in his heliocentric model. ... The phases of Venus could not be explained by Ptolemy's Geocentric Model. Galileo knew that the Roman Catholic Church was incorrect.

Answer:

Over time, the Sun's differential rotation rates cause its magnetic field to become twisted and tangled. The "tangles" in the magnetic field lines can produce very, very strong localized magnetic fields. Places where "ropes" of bundled field lines "break" the surface of the Sun are active regions where sunspots form.

Answer:

Na(s) + H₂O (l) → NaOH(aq) + H₂(g).

Explanation:

answer is this thank you I hope it helps you pls like

Answer:

Mass = 2.59 g

Explanation:

Given data:

Mass of AgS = 3.45 g

Mass of silver = ?

Solution:

Number of moles of AgS:

Number of moles = mass/molar mass

Number of moles = 3.45 g/ 139.93 g/mol

Number of moles = 0.024 mol

1 mole of AgS  contain 1 mole of Ag.

0.024 mol contain 0.024 mol of Ag.

Mass of silver:

Mass = number of moles × molar mass

Mass = 0.024 mol × 107.86 g/mol

Mass = 2.59 g

Answer:

Chlorine gas.

Explanation:

Hello!

In this case, the undergoing chemical reaction is:

[tex]2Na+Cl_2\rightarrow 2NaCl[/tex]

Thus, given the moles of reacting both sodium and chlorine, we compute the moles of sodium chloride yielded by each reactant by considering the 2:2 and 1:2 mole ratios:

[tex]n_{NaCl}^{by\ Na}=6.70molNa*\frac{2molNaCl}{2molNa}=6.70molNaCl \\\\n_{NaCl}^{by\ Cl_2}=3.20molCl_2*\frac{2molNaCl}{1molCl_2}=6.40molNaCl[/tex]

Thus, since chlorine yields less moles of sodium chloride, we infer it is the limiting reactant.

Best regards!

Answer: ENERGY: A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another; the levels in the food chain are producers, primary consumers, higher-level consumers, and finally decomposers. These levels are used to describe ecosystem structure and dynamics.

MATTER: When one organism eats another, the matter, or carbon, nitrogen, and other essential elements, are transferred from one to the other. These elements move from the producers, to the consumers, and eventually to the decomposers, cycling the matter through the ecosystem.

Explanation: look up

Answer:

The Sugar Act (1764),

The Currency Act (1764),

The Quartering Act (1765),

The Stamp Act (1765)

Explanation:

All of these Led to the american Revolution.

Answer:1

Explanation: friction is showing us how in the past

Answer: B -2.37 -0.34

Explanation: A P E X

The redox reaction consists of the reduction and the oxidation halves and involves the transfer of electrons. The overall voltage for the Mg and Cu is 0.34 - (-2.37). Thus, option C is correct.

A nonspontaneous redox reaction is the loss and gain of the electrons when an external source of voltage is applied to initiate the electrochemical reaction.

The overall voltage of the redox reaction can be given by the oxidation and the reduction of half of the cell as,

Oxidation half: Mg(s) → Mg₂⁺ + 2e⁻  E° = -2.37 v

Reduction half: Cu₂⁺ + 2e⁻ → Cu(s)  E° = + 0.34 v

The overall voltage of the cell (E° cell) is calculated as,

E° cell = E°(reduction) - E°(oxidation)

= +0.34 - (-2.37)

= 2.71 v

Therefore, option C. 0.34 - (-2.37) is the overall voltage for the nonspontaneous redox reaction.

Learn more about redox reaction here:

https://brainly.com/question/14217644

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Your question is incomplete, but most probably your full question was, What is the overall voltage for a redox reaction with the half-reactions Mg(s) → Mg₂⁺ + 2e⁻ and Cu₂⁺ + 2e⁻ → Cu(s)?

A. -2.37 - 0.34

B. 0.34 - 2.37

C. 0.34 - (-2.37)

D. 2.37 - 0.34

Answer:

[tex]velocity = \frac{displacement}{time} \\ = \frac{5}{6} \\ velocity = \frac{5}{6} m {s}^{ - 1} [/tex]

Answer:

1000

Explanation:

Answer:

C) 301.8

Explanation:

Hello!

In this case, since the solution is composed by water and salt, the total resulting mass comes up from adding the mixed mass of each one:

[tex]m_{sol}=m_{w}+m_{salt}[/tex]

Thus, we plug in to obtain:

[tex]m_{sol}=200.4g+101.42g\\\\m_{sol}=301.8g[/tex]

Therefore, the answer should be C) 301.8 as it has four significant figures.

Best regards!

Answer:

Exothermic

Explanation:

We as humans do not absorb heat. A good way to think about it is that when we workout we use energy from our body which causes our body temperature to rise. The energy used from food maintains our blood, respiration, and other systems in optimal condition. This requires energy from our body which ends up leaving the body as heat.

Answer

There is not as much sunlight underwater and therefore less energy can be absorbed therefore a slower process of photosynthesis.    

Explanation:

Answer:

Explanation:

The answer is 32°F or 0° Celsius.

Hope it helped you.

Answer:

In an exothermic reaction, the products are at a lower energy than the reactants. The difference between the energy of the reactants and the energy of the products is called the enthalpy change (∆H) of the reaction. For an exothermic reaction, the enthalpy change is always negative.

Answer:

The natural abundance of Re-185 is 40% and of Re-187 is 60%

Explanation:

Relative atomic mass is defined as the sum of the mass of each isotope times its relative abundances.

Is Rhenium has only 2 isotopes and the abundances are X and Y we can write:

X + Y = 1 (1)

And:

185X + 187Y = 186.2 (2)

Where X is abundance of Re-185 and Y abundance of Re-187

Replacing (1) in (2):

185X + 187(1-X) = 186.2

185X + 187-187X = 186.2

-2X = -0.8

X = 0.4 = 40%

And Y = 100% - 40% = 60%

Answer: 1) chemical change 2) chemical properties 3) ratio? 4) created nor destroyed

Explanation: 1) Matter is composed of exceedingly small particles called atoms. An atom is the smallest unit of an element that can participate in a chemical change. 2) A macroscopic sample of an element contains an incredibly large number of atoms, all of which have identical chemical properties. 3) A compound consists of atoms of two or more elements combined in a small, whole-number ratio. In a given compound, the numbers of atoms of each of its elements are always present in the same ratio. 4) Atoms are neither created nor destroyed during a chemical change, but are instead rearranged to yield substances that are different from those present before the change

Answer:

Potassium nitrate is a chemical compound with the chemical formula KNO3. It is an ionic salt of potassium ions K+ and nitrate ions NO3−, and is therefore an alkali metal nitrate. It occurs in nature as a mineral, niter (or nitre in the UK). It is a source of nitrogen, and nitrogen was named after niter.

Explanation:

Answer:

the population of the region

Hope this helps :)

Answer:

You're answer is correct. The third answer is correct.

Explanation:

Producers have the most energy, since they gain energy directly from the sun. Their energy is then passed up this upside down pyramid, which the energy is decreased by about 10% each time.

#teamtrees #WAP (Water And Plant)

Answer:

i will tell your teacher that u uding online cheats to answer yout homeworks hhaahaha

Explanation:

good luck brooo hahahha

Answer:

150.08 g

Explanation:

According the law of conservation of mass, mass can neither be created nor destroyed but is converted from one form to another.

As a result of this, the total mass of reactants must be equal to the total mass of products.

If this is so, we have been told that the mass of AgCl is 150.15 g, the total mass of products is 300.23g.

Therefore; mass of NaNO3 = 300.23 g - 150.15 g = 150.08 g

Answer:

Look at the picture below

Explanation:

Answer:

B,C,F

Explanation:

Answer:

b c f

Explanation: