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4 years ago

How many grams (m) of glucose are in 165 ml of a 5.50% (m/v) glucose solution? express your answer numerically in grams?

1 answer:

6 0

mass of glucose = 0.055 *165 = 9.075 g

vol of methyl alc = 0.185 * 1.87 = 0.346 L = 346 ml

% NaCl ( m/v ) = mass NaCl * 100/ vol of soln

or Vol of Soln = mass NaCl / % NaCl (m/v)

= 32.1 * 100 / 6 = 535 ml the total vol of soln

You might be interested in

What is the mass of 4.5 x 10^22 molecules of hydrogen peroxide (H2O2)? Show your work in the space below.

valentinak56 [21]

Given :

Number of molecules of hydrogen peroxide, N = 4.5 × 10²².

To Find :

The mass of given molecules of hydrogen peroxide.

Solution :

We know, 1 mole of every compound contains Nₐ = 6.022 × 10²³ molecules.

So, number of moles of hydrogen peroxide is :

$n = \dfrac{N}{N_a}\\\\n = \dfrac{4.5\times 10^{22}}{6.022\times 10^{23}}\\\\n = 0.0747 \ moles$

Now, mass of hydrogen peroxide is given as :

m = n × M.M

m = 0.0747 × 34 grams

m = 2.54 grams

Hence, this is the required solution.

6 0

3 years ago

Plzzz help do your best to answer these questions

vovikov84 [41]

The empirical formula is the simplest formula of a chemical compound.

To find the empirical formula, we take the following steps;

Divide the percentage by mass of each element by its relative atomic mass.
Divide the quotient of each by the lowest value obtained instep 1 above
Write the result of step 2 above as the subscript following each atom.

1) O - 88.10/16, H - 11.190/1

O - 5.5, H - 11.19

O - 5.5/5.5, H - 11.19/5.5

O - 1, H - 2

Empirical formula = OH2

2) C - 41.368/12 H - 8.101/1, N - 32.162/14, O - 18.369/16

C - 3, H - 8, N - 2, O - 1

C - 3/1, H - 8/1 N - 2/1 O - 1/1

C - 3, H - 8, N - 2, O - 1

Empirical formula = C3H8N2O

To obtain the molecular formula where n = number of atoms of each element;

Molecular weight = 174.204 g/mol

[ 3(12) + 8(1) + 2(14) + 16]n = 174

n= 174/88

n = 2 (to the nearest whole number)

Hence, we have;

[C3H8N2O]2

The molecular formula is C6H16N4O2

3) C - 19.999/12, H - 6.713/1, N - 46.646/14, O - 26.641/16

C - 2, H - 7, N - 3, O - 2

C - 2/2, H - 7/2, N - 3/2, O - 2/2

C - 1, H - 4, N - 2, O - 1

Empirical formula - CH4N2O

brainly.com/question/1363167

5 0

3 years ago

Perform the calculation and record the answer with the correct number of significant figures.

kotykmax [81]

The question is incomplete, here is the complete question:

A. (6.5-6.10)/3.19

B. (34.123 + 9.60) / (98.7654 - 9.249)

Answer:

For A: The answer becomes 0.1

For B: The answer becomes 0.4884

Explanation:

Significant figures are defined as the figures present in a number that expresses the magnitude of a quantity to a specific degree of accuracy.

Rules for the identification of 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: 664, 6.64 and 66.4 all have three significant figures.
All zeros between the integers are always significant. For example: 5018, 5.018 and 50.18 all have four significant figures.
All zeros preceding the first integers are never significant. For example: 0.00058 has two significant figures.
All zeros after the decimal point are always significant. For example: 2.500, 25.00 and 250.0 all have four significant figures.
All zeroes used solely for spacing the decimal point are not significant. For example: 10000 has one significant figure.

Rule applied for addition and subtraction:

The least precise number present after the decimal point determines the number of significant figures in the answer.

Rule applied for multiplication and division:

In case of multiplication and division, the number of significant digits is taken from the value which has least precise significant digits