Why do you think it would be important for scientists to test local water?

Answer:

60g of LiNO3 are required

Explanation:

Calculate the amount of solute, in grams or milliliters, to prepare...

The percentage mass/volume %(m/v) is defined as the mass in grams of the solute in 100mL of solution

To solve this question we must know that in a 37.5% (m/v) of LiNO3 you have 37.5g of LiNO3 in 100mL of solution.

Thus, to prepare 160mL are required:

160mL * (37.5g / 100mL) =

mass percent = (mass of element in 1 mole of compound / mass of 1 mole of compound) x 100. The formula for a solution is:

mass percent = (grams of solute / grams of solute plus solvent) x 100. or.

mass percent = (grams of solute / grams of solution) x 100. The final answer is given as %.

Hope this helps!!

Answer:

[tex]\Delta H_{comb}=2043.85kJ/mol[/tex]

Explanation:

Hello there!

In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:

[tex]\Delta H_r=-\Delta H_{comb}=3\Delta _fH_{CO_2}+4\Delta _fH_{H_2O}-\Delta _fH_{C_3H_8}-3\Delta _fH_{O_2}[/tex]

Thus, given the values of the enthalpies of formation on the attached file, we obtain:[tex]-\Delta H_{comb}=3(-393.5kJ/mol)+4(-241.8kJ/mol)-(-103.85kJ/mol)-3(0kJ/mol)\\\\-\Delta H_{comb}=-2043.85kJ/mol\\\\\Delta H_{comb}=2043.85kJ/mol[/tex]

Best regards!

Answer:

A

Explanation:

Each DNA sequence that contains instructions to make a protein is known as a gene. The size of a gene may vary greatly, ranging from about 1,000 bases to 1 million bases in humans.

Answer:

li3po4

Explanation:

Answer:

1

Explanation:

one volume of nitrogen to react

Answer:

0.20 g/L

Explanation:

Step 1: Calculate the molar mass of the gas (M)

At T = 350 °C = 623 K and P = 1 atm (we will assume this data), the density (ρ) of the gas is 0.087 g/L. We can calculate the molar mass of the gas using the following expression.

ρ = P × M/R × T

M = ρ × R × T/P

M = 0.087 g/L × (0.0821 atm.L/mol.K) × 623 K/1 atm = 4.5 g/mol

Step 2: Calculate the density of the gas at STP

At standard temperature (T = 273.15 K) and standard pressure (P = 1 atm), the density of the gas is:

ρ = P × M/R × T

ρ = 1 atm × 4.5 g/mol /(0.0821 atm.L/mol.K) × 273.15 K = 0.20 g/L

Answer:

a.Provide the body which shape and protection.

Explanation:

Bones usually gives us shape as well as protects our innner organs.

so if it helps don't forget to like and Mark me

Answer:

Iodine is a non-metal, but it is lustrous (lustrous is the property of metal) in nature.

Answer:

Streak

Explanation:

Hope it Help

Thanks me later

Answer: D Avogadro’s Number

Explanation:

Another name for a mole is Avogadro's number. option D) is correct.

What is a Mole?

A mole refers to the amount of a substance that contains as many elementary units as can be found in 12g of Carbon-12. It can also be a number of a substance /particles, such as atoms or ions. molecules or electrons.  The number of particles is approximately 6.02* 10²³ in magnitude and is called Avogadro's number of particles. it can be denoted with 'mol'.

Formula for calculating mole.

n = N/Nₐ

Where,

n = number of moles of the substance (or elementary entity)

N = total number of elementary entities in the sample

Nₐ= Avogadro constant.

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Answer:

a) the final temperature of the air is 500° R

b) the amount of specific entropy produced is 0.0758 Btu/lb-°R  

Explanation:

Given the data in the question;

Air at 500° R = [tex]T_i[/tex]

Using first law of thermodynamic;

δQ = dU + W

now, since the vessel is insulated, the transfer is zero, work done also is zero since there is also no external work done.

δQ = dU + W

0 = dU + 0

dU = 0

[tex]u_f[/tex] - [tex]u_i[/tex] = 0

[tex]u_f[/tex] = [tex]u_i[/tex]

hence, change in internal energy is 0

Now, since the ideal internal energy is a function of temperature, the temperature will also remain the same;

[tex]T_f = T_i[/tex]

F = 500° R

Therefore, the final temperature of the air is 500° R

b)

given that; initial volume is one-third of the total volume

V₁ = [tex]\frac{1}{3}[/tex]V₂

3V₁ = V₂

3 = V₂/V₁

Now, we take the value of gas constant R from air property table;  gas constant R = 0.069 Btu/lb-R  

so we calculate the entropy change;

Δs = [tex]c_v[/tex]In( [tex]\frac{T_2}{T_1}[/tex] ) + R.In( [tex]\frac{V_2}{V_1}[/tex] )

we substitute

Δs = [tex]c_v[/tex]In( [tex]\frac{500}{500}[/tex] ) + 0.069 × In( 3 )

Δs = 0 + [0.069 × In( 3 )]

Δs = 0 + [0.069 × 1.0986]

Δs = 0.0758 Btu/lb-°R  

Therefore, the amount of specific entropy produced is 0.0758 Btu/lb-°R  

Insulated vessels separate the environment of the outer and the inner system. The final temperature is 500 degrees R and 0.0758 Btu/lb- degree R is the entropy.

The temperature is the measure of the hot or the coldness of the system.  The first law of the thermodynamics is used to measure the final temperature of the system:

[tex]\rm \Delta Q = \rm \Delta U + W[/tex]

The work done will be zero as the system is insulated and no external work is being done.

[tex]\begin{aligned} \rm 0 &= \rm \Delta U + 0\\\\\rm U_{f} - U_{i} &= 0\\\\\rm U_{f} &= \rm U_{i} \end{aligned}[/tex]

Hence, the change in the internal energy is zero. Thus, the final temperature will remain the same,

[tex]\rm T_{f} = \rm T_{i} = 500 ^{\circ} \rm R[/tex]

Now, as we know, the initial volume is one-third of the total volume then,

[tex]\begin{aligned} \rm V_{1} &= \rm \dfrac{1}{3} V_{2}\\\\\rm 3V_{1}&= \rm V_{2}\\\\3 &= \rm \dfrac{V_{1}}{V_{2}}\end{aligned}[/tex]

The change in entropy is calculated as:

[tex]\begin{aligned} \rm \Delta S &= \rm C_{v} ln ( \dfrac{T_{2}}{T_{1}}) + R \times ln ( \dfrac{V_{2}}{V_{1}}) \\\\&= 0 + [0.069 \times \rm ln( 3 )]\\\\& = 0.0758 \;\rm Btu/lb-^{\circ}R \end{aligned}[/tex]

Therefore, the entropy produced is 0.0758 Btu/lb- degree R.

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Answer:

the answer is 4

Explanation:

your welcome lol

Answer:

ftb

Explanation:

Answer:

Explanation:

The preceding chapter introduced the use of element symbols to represent individual atoms. When atoms gain or lose electrons to yield ions, or combine with other atoms to form molecules, their symbols are modified or combined to generate chemical formulas that appropriately represent these species. Extending this symbolism to represent both the identities and the relative quantities of substances undergoing a chemical (or physical) change involves writing and balancing a chemical equation. Consider as an example the reaction between one methane molecule (CH4) and two diatomic oxygen molecules (O2) to produce one carbon dioxide molecule (CO2) and two water molecules (H2O). The chemical equation representing this process is provided in the upper half of Figure 1, with space-filling molecular models shown in the lower half of the figure.

Answer:

no sure

Explanation:

Answer:

The scaling factor is 5.

Explanation:

Hello there!

In this case, since the scaling factor is defined as the ratio of the molar mass of the molecular formula (complete) to the empirical formula (simplified), it is possible to compute it for the empirical formula of CH2O whose molar mass is 30 g/mol (12+2+16) as shown below:

[tex]sf=150/30=5[/tex]

Therefore, we can also infer that the molecular formula would be:

[tex]C_5H_1_0O_5[/tex]

Best regards!

As provided in the question, the pH of a solution is equal to the negative logarithm of the H₃O⁺ concentration in the solution (the square brackets denote the molar concentration).

We are given a solution with an H₃O⁺ concentration of 5.6 × 10⁻⁹ M. So, the pH of this solution would be:

pH = -log[H₃O⁺] = -log(5.6 × 10⁻⁹ M) = 8.25.

A pH that is equal to 7 is neutral; less than 7, acidic; and greater than 7, basic. As 8.25 is greater than 7, this solution is basic.

Answer:

because we need it to breathe

Explanation:

we breathe in oxygen and release carbon dioxide

Answer:

Ok i have a really weird theory.

Oxygen actually kills us we just don't know it yet. We need it too live but something in it also poisons us and causes us to die in around 100 years from birth. that's why we all die

real answer

we need it to breathe, when we breath we inhale in oxygen and release carbon dioxide which allows trees to grow and they produce more oxygen. We cant rely on anything else because oxygen is important and without it we die. Oxygen is one of the purist airs.

Answer:

0.01125

Explanation:

:b

Answer:

[tex]V_1=7.5L[/tex]

Explanation:

Hello there!

In this case, according to the Charles' law equation which help us to understand the directly proportional relationship between volume and temperature:

[tex]\frac{V_2}{T_2}= \frac{V_1}{T_1}[/tex]

Thus, by solving for the initial volume, V1, and making sure we use the temperatures in Kelvin, we can calculate the final volume as shown below:

[tex]V_1= \frac{V_2T_1}{T_2} \\\\V_1= \frac{5.0L*(147+273)K}{(7.0+273)K} \\\\V_1=7.5L[/tex]

Best regards!

Answer:

Explanation:

Convert molecules to moles:

1 mole of NaNO₃= 6.02 x 10^23 molecules of NaNO₃

7.3 x10^24/(6.02 x 10^23)=12mol NaNO₃

Find molar mass:

NaNO₃=1 mole of Na and 1mole of N and 3mole of O

Find grams:

14.01g x 12= 168.12 g of N

Answer:  An energy resource is something that can produce heat, power life, move objects, or produce electricity

Answer:

I do not know the Answer I'm just trying to get my point

Explanation:

Thank You

The two realistic demands protestors could bring forward in their peaceful protest include:

Thus it is referred to an individual which publicly demonstrates opposition to something.One of the roles of the government is to protect lives and properties.

Making realistic demands during a peaceful protest is looked into in most cases.

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Answer:

2365 g

Explanation: