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Significant digits are the number of digits that reflect the precision of a measurement or number.

Delvig [45]

Answer:

True

Explanation:

Significant digits are numbers that helps to present the precision of measurements calculations.

Numbers that do not contribute to the precision of a reading should not be counted as significant.

There are rules of assigning significant numbers:

Leading or trailing zeros are insignificant and should only be counted as a place holder.
All non-zero digits are significant
Zeroes between non-zero digits are significant.
Leading zeros in a decimal are significant before the number.
All the numbers in a scientific notation are significant.

5 0

3 years ago

How Many Atoms Are In 356.13 Grams Of Sn

s344n2d4d5 [400]

<span>There are three atoms of Sn (Stannous or Tin) in</span> 356.13 g of Sn.

<span>One atom of Sn has the atomic mass (m</span>ₐ<span>) of </span>118,71u which means:

356.13/118.71=3 atoms of Sn

The mass number (symbol A) also called atomic mass number or nucleon number is the total number of protons and neutrons in an atomic nucleus. It determines the atomic mass of atoms and it is in the periodic table.

8 0

2 years ago

A tetraphenyl phosphonium chloride (TPPCl) powder (FW=342.39) is 94.0 percent pure. How many grams are needed to prepare 0.45 L

slega [8]

Answer:

5.41 g

Explanation:

Considering:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

Or,

$Moles =Molarity \times {Volume\ of\ the\ solution}$

Given :

For tetraphenyl phosphonium chloride :

Molarity = 33.0 mM = 0.033 M (As, 1 mM = 0.001 M)

Volume = 0.45 L

Thus, moles of tetraphenyl phosphonium chloride :

$Moles=0.033 \times {0.45}\ moles$

Moles of TPPCl = 0.01485 moles

Molar mass of TPPCl = 342.39 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$0.01485\ g= \frac{Mass}{342.39\ g/mol}$

Mass of TPPCl = 5.0845 g

Also,

TPPCl is 94.0 % pure.

It means that 94.0 g is present in 100 g of powder

5.0845 g is present in 5.41 g of the powder.

<u>Answer - 5.41 g</u>

5 0

3 years ago

Oxygen gas generated in the thermal decomposition of potassium chlorate is collected over water. The volume of gas collected is

Leya [2.2K]

The mass of oxygen collected from the thermal decomposition of potassium chlorate at a temperature of 297 K and 762 mmHg is 0.16 g

<h3>How to determine the mole of oxygen produced </h3>

We'll begin by obtaining the number of mole of oxygen gas produced from the reaction. This can be obtained by using the ideal gas equation as illustrated below:

Volume (V) = 0.128 L
Temperature (T) = 297 K
Pressure (P) = 762 – 22.4 = 739.6 mmHg
Gas constant (R) = 62.363 mmHg.L/Kmol
Number of mole (n) =?

PV = nRT

739.6 × 0.128 = n × 62.363 × 297

Divide both sides by 62.363 × 297

n = (739.6 × 0.128) / (62.363 × 297)

n = 0.0051 mole

Thus, the number of mole of oxygen gas produced is 0.0051 mole

<h3>How to determine the mass of oxygen collected</h3>

Haven obtain the number of mole of oxygen gas produced, we can determine the mass of the oxygen produced as follow:'

Mole = 0.0051 mole
Molar mass of oxygen gas = 32 g/mole
Mass of oxygen =?

Mole = mass / molar mass

0.0051 = mass of oxygen / 32

Cross multiply

Mass of oxygen = 0.0051 × 32

Mass of oxygen = 0.16 g

Thus, we can conclude that the mass of oxygen gas collected is 0.16 g

Learn more about ideal gas equation:

brainly.com/question/4147359

#SPJ1

5 0

1 year ago

If 52500 J of heat is used to heat a 10200g block of metal and

Angelina_Jolie [31]

Answer:

45.95 Jkg^-1°C^-1

Explanation:

as specific heat capacity = heat energy / mass × delta

temperature

=52500/10.2×112

=45.95 Jkg^-1°C^-1

5 0

2 years ago