Hợp chất X gồm 2 nguyên tố A và O.Trong đó A cs hóa trị IV.A chiếm 50% về khối lượng.

Is the cyanide ion a strong or weak base?

11111nata11111 [884]

It's a weak base bacause H C N is weak

4 0

3 years ago

If you are using a thermometer you are measuring the

Slav-nsk [51]

Temperature of somewhere.

6 0

3 years ago

Which statement below best describes mutations?

Studentka2010 [4]

Answer:

C. Mutations are a change in DNA or a chromosome and can be helpful, harmful or may have no affect.

Explanation:

Mutations are spontaneous random changes that occurs in the genetic make up of an organisms. Mutations are rare and their rate of occurrence is random.
Mutations may occur on the gene level known as gene mutations or at chromosome levels called chromosomal mutations.
Mutations may be beneficial, harmful or have no effect on a given organisms. Harmful mutations cause disorders that may lead to abnormality or death of an organisms. Beneficial mutations improve an organisms adaptability to the environment.

8 0

3 years ago

18 An important environmental consideration is the appropriate disposal of cleaning solvents. An environmental waste treatment c

Katyanochek1 [597]

Answer:

a) Percentage by mass of carbon: 18.3%

Percentage by mass of hydrogen: 0.77%

b) Percentage by mass of chlorine: 80.37%

c) Molecular formula: $C_{2} H Cl_{3}$

Explanation:

Firstly, the mass of carbon must be determined by using a conversion factor:

$0.872g CO _{2} *\frac{12g C}{44g CO_{2} } = 0.238g CO_{2}$

The same process is used to calculate the amount of hydrogen:

$0.089g H_{2}O*\frac{2g H}{18g H_{2}O } = 0.010g H$

The percentage by mass of carbon and hydrogen are calculated as follows:

%C $\frac{0.238g}{1.3g} *100%$ = 18.3%

%H $\frac{0.010g}{1.3g} *100%$ =0.77%

From the precipation data it is possible obtain the amount of chlorine present in the compound:

$1.75 AgCl*\frac{35.45g Cl}{143.45g AgCl}$ = 0.43g AgCl

Let's calculate the percentage by mass of chlorine:

%Cl= $\frac{0.43g}{0.535g} * 100%$ = 80.37%

Assuming that we have 100g of the compound, it is possible to determine the number of moles of each element in the compound:

$18.3g C*\frac{1mol C}{12g C} = 1.52mol C$

$0.77g H*\frac{1mol H}{1g H} = 0.77mol H$

$80.37gCl*\frac{1molCl}{35.45g Cl} = 2.27mol Cl$

Dividing each of the quantities above by the smallest (0.77mol), the subscripts in a tentative formula would be

$C=\frac{1.52}{0.77} = 1.97$ ≈ 2

$H = \frac{0.77}{0.77} = 1$

$Cl =\frac{2.27}{0.77}=2.94$ ≈3

The empirical formula for the compound is:

$C_{2} H Cl_{3}$

The mass of this empirical formula is:

mass of C + mass of H + mass of Cl= 24g +1+ 106.35 =131.35g

This mass matches with the molar mass, which means that the supscript in the molecular formula are the same of the empirical one.

5 0

3 years ago

List at least 4 properties of magnetic field lines

Rama09 [41]

1. No two magnetic lines intersect
2.They always form closed loops
3. Outside they seems to travel from north to south and inside south to north
4. It is vector quantity.

7 0

3 years ago