What’s at the end of the leg bones?

Iodine-138 decays by beta decay. What element does it produce?

iVinArrow [24]

${xe}^{138}$

Explanation:

the bottom number would be 54. This is because you add one to 53 to make it 54 and you add 0 to 138.

4 0

2 years ago

Read 2 more answers

In a chromatography experiment, chlorophyll pigments are separated using paper. What is the stationary phase in this experiment?

Bond [772]

Answer:
The stationary phase in chromatography experiment is paper.

Explanation:
In chromatography experiment, the stationary phase is defined as the fixed substance that is necessary to start chromatography. In our case, this fixed substance is paper, so that makes paper our stationary phase.

Hope this helps :)

4 0

3 years ago

Read 2 more answers

Substances that are readily combustible or may cause fire through friction

Dvinal [7]

Answer :

Flammable substances

Explanation :

Flammable substances will catch fire and continue to burn when they contact an ignition source like a spark or a flame.

For example, methanol is a flammable liquid.

A flammable solid may also catch fire through friction. Matches are flammable solids.

3 0

3 years ago

He generic metal a forms an insoluble salt ab(s) and a complex ac5(aq). the equilibrium concentrations in a solution of ac5 were

elena55 [62]

Balanced chemical reaction: A + 5C ⇄ AC₅.
[A] = 0.100 M; equilibrium concentration.
[C] = 0.0380 M.
[AC₅] = 0.100 M.
Kf = [AC₅] / ([A] · [C]⁵).
Kf = 0.100 M ÷ (0.100 M · (0.0380 M)⁵.
Kf = 12620658.54 = 1,26·10⁷.
The formation constant can be calculated when chemical equilibrium is reached, when the forward reaction rate is equal to the reverse reaction rate.

7 0

3 years ago

A gaseous mixture composed of 20% CH4, 30% C2H4, 35% C2H2, and 15% C2H20. What is the average molecular weight of the mixture? a

Semenov [28]

Answer: The correct answer is Option d.

Explanation:

We are given:

Mass percentage of $CH_4$ = 20 %

So, mole fraction of $CH_4$ = 0.2

Mass percentage of $C_2H_4$ = 30 %

So, mole fraction of $C_2H_4$ = 0.3

Mass percentage of $C_2H_2$ = 35 %

So, mole fraction of $C_2H_2$ = 0.35

Mass percentage of $C_2H_2O$ = 15 %

So, mole fraction of $C_2H_2O$ = 0.15

We know that:

Molar mass of $CH_4$ = 16 g/mol

Molar mass of $C_2H_4$ = 28 g/mol

Molar mass of $C_2H_2$ = 26 g/mol

Molar mass of $C_2H_2O$ = 48 g/mol

To calculate the average molecular mass of the mixture, we use the equation:

$\text{Average molecular weight of mixture}=\frac{_{i=1}^n\sum{\chi_im_i}}{n_i}$

where,

$\chi_i$ = mole fractions of i-th species

$m_i$ = molar masses of i-th species

$n_i$ = number of observations

Putting values in above equation:

$\text{Average molecular weight}=\frac{(\chi_{CH_4}\times M_{CH_4})+(\chi_{C_2H_4}\times M_{C_2H_4})+(\chi_{C_2H_2}\times M_{C_2H_2})+(\chi_{C_2H_2O}\times M_{C_2H_2O})}{4}$

$\text{Average molecular weight of mixture}=\frac{(0.20\times 16)+(0.30\times 28)+(0.35\times 26)+(0.15\times 42)}{4}\\\\\text{Average molecular weight of mixture}=6.75$

Hence, the correct answer is Option d.

3 0

3 years ago