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3 years ago

Give the number of significant figures: 0.011 cm

Chemistry

2 answers:

faust18 [17]3 years ago

8 0

It would be only two because you would not count the zeros to the left even if there is a decimal point :)

Simora [160]3 years ago

3 0

Answer: 2 significant figures

Explanation:

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

Rules for significant figures:

Digits from 1 to 9 are always significant and have infinite number of significant figures.

All non-zero numbers are always significant. For example: 654, 6.54 and 65.4 all have three significant figures.

All zero’s between integers are always significant. For example: 5005, 5.005 and 50.05 all have four significant figures.

All zero’s preceding the first integers are never significant. For example: 0.0078 has two significant figures.

All zero’s after the decimal point are always significant. For example: 4.500, 45.00 and 450.0 all have four significant figures.

Thus 0.011 has 2 significant figures.

You might be interested in

A pharmacist has a 12% solution of boric acid and a 20% solution of boric acid. How much of each must he use to make 80 grams of

Iteru [2.4K]

Answer:

He must use 50g of the 12% solution and 30 g of the 20% solution.

Explanation:

Call x the amount of 12% boric acid solution to be used.

The content of acid of that is: 0.12x

Since he wants to make 80 grams of solution, the amount of 20% boric acid solution to be used is 80 - x.

The content of acid of that is{ 0.20(80 - x).

The final solution is 15% concentrated.

The content of boric acid of that is 0.15 × 80 g.

Now you have can write your equation:

$0.12x+0.20(80-x)=0.15\times 80$

Solve:

$0.12x + 16 - 0.20x=12\\\\-0.08x=12-16\\\\0.08x=4\\\\x=4/0.08\\\\x=50$

That is 50 grams of the 12% solution of boric acid.

Calculate the amount of the 20% solution of boric acid:

$80-x=80-50=30$

That is 30 grams.

Then, he must use 50g of the 12% solution and 30 g of the 20% solution.

5 0

3 years ago

Problem PageQuestion The airbags that protect people in car crashes are inflated by the extremely rapid decomposition of sodium

Shalnov [3]

Answer:

1. 2NaN₃(s) → 2Na(s) + 3N₂(g)

2. 14.5 g NaN₃

Explanation:

The answer is incomplete, as it is missing the required values to solve the problem. An internet search shows me these values for this question. Keep in mind that if your values are different your result will be different as well, but the solving methodology won't change.

" The airbags that protect people in car crashes are inflated by the extremely rapid decomposition of sodium azide, which produces large volumes of nitrogen gas. 1. Write a balanced chemical equation, including physical state symbols, for the decomposition of solid sodium azide (NaN₃) into solid sodium and gaseous dinitrogen. 2. Suppose 71.0 L of dinitrogen gas are produced by this reaction, at a temperature of 16.0 °C and pressure of exactly 1 atm. Calculate the mass of sodium azide that must have reacted. Round your answer to 3 significant digits. "

1. The reaction that takes place is:

2NaN₃(s) → 2Na(s) + 3N₂(g)

2. We use PV=nRT to calculate the moles of N₂ that were produced.

P = 1 atm

V = 71.0 L

n = ?

T = 16.0 °C ⇒ 16.0 + 273.16 = 289.16 K

1 atm * 71.0 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 289.16 K

n = 0.334 mol

Now we convert N₂ moles to NaN₃ moles:

0.334 mol N₂ * $\frac{2molNaN_{3}}{3molN_2}$ = 0.223 mol NaN₃

Finally we convert NaN₃ moles to grams, using its molar mass:

0.223 mol NaN₃ * 65 g/mol = 14.5 g NaN₃

6 0

3 years ago

What is the hydronium and hydroxide concentrations of a solution that is 5.0 x 10-3 M H2SO4.

Maksim231197 [3]

The hydronium and hydroxide concentrations of a solution that is 5.0 x 10-3 M H2SO4 is 2.7.

pH= -log[H+] - (i)

10^-3=H2So4

H+= 2×10-3

here ,

h2so4 ——— 2[H+] + so4^2-

thus [H+]= 2*10^(-3) because hydrogen ion has two moles

pH= -log[H+]

pH= -log(2×10^-3)

pH= 3-log2

pH= 3-log2pH= 2.7

The pH is 2.7

PH is the degree of alkalinity and acidicity in a solution.

Therefore, The hydronium and hydroxide concentrations of a solution that is 5.0 x 10-3 M H2SO4 is 2.7

Learn more about pH from the link below.

https://brainly.in/question/9937410

4 0

2 years ago

Which is an important question to consider when creating an environmental policy?

morpeh [17]

Answer: is the benefit worth the cost?

Explanation: for those on edge :)

4 0

3 years ago

Read 2 more answers

There are on average 43 g of sugar and 355 mL can of soda please calculate the molarity of sugar in the can of soda the molar ma

vfiekz [6]

Explanation:

Given :

Amount of solute - sucrose (C12H22O11) = 41 g

Amount of solvent -soda = 355-mL

Molarity of the solution with respect to sucrose= ?

Molarity(M) is a unit of concentration measuring the number of moles of a solute per liter of solution. The SI unit of molarity is mol/L.

Formula to find the molarity of solution :

Molarity =

Amount of solvent is given in mL, let’s convert to L :

1 L = 1000 mL

Therefore, 355 mL in L will be :

= 0.355 L

We have the amount of solute in g, let’s calculate the number of moles first :

Number of moles (n) =

Molar mass of C12H22O11 = 342.29 g/mol.

Therefore, n =

= 0.119 moles.

8 0

3 years ago