Which one is nonspecific defense of the body

Which of the following is considered a form of technology?

anygoal [31]

Answer:

The answer is B. Hope this helps! please give me brainliest!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! =)

8 0

3 years ago

Read 2 more answers

When 500.0 g of water is decomposed by electrolysis and the yield of hydrogen is only 75.3%, how much hydrogen chloride can be m

Evgen [1.6K]

The amount of hydrogen chloride that can be made is 1064 g

Why?

The two reactions are:

2H₂O → 2H₂ + O₂ 75.3 % yield

H₂ + Cl₂ → 2HCl 69.8% yield

We have to apply a big conversion factor to go from grams of water (The limiting reactant), to grams of HCl, the final product. We have to be very careful with the coefficients and percentage yields!

$500.0gH_2O*\frac{1moleH_2O}{18.01 gH_2O}*\frac{2 moles H_2}{2 moles H_2O}*\frac{2.015g H_2}{1 mole H_2}*\frac{75.3 actual g}{100 theoretical g}=42.12 g H_2$

$42.12H_2*\frac{1 mole H_2}{2.015gH_2}*\frac{2 moles HCl}{1 mole H_2}*\frac{36.46g}{1 mole HCl}*\frac{69.8 actualg}{100 theoreticalg} =1064gHCl$

Have a nice day!

#LearnwithBrainly

7 0

4 years ago

What is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n =

Lady bird [3.3K]

Answer:

$4.86\times10^{-7}\ \text{m}$

Explanation:

R = Rydberg constant = $1.09677583\times 10^7\ \text{m}^{-1}$

$n_1$ = Principal quantum number of an energy level = 2

$n_2$ = Principal quantum number of an energy level for the atomic electron transition = 4

Wavelength is given by the Rydberg formula

$\lambda^{-1}=R\left(\dfrac{1}{n_1^2}-\dfrac{1}{n_2^2}\right)\\\Rightarrow \lambda^{-1}=1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\\\Rightarrow \lambda=\left(1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\right)^{-1}\\\Rightarrow \lambda=4.86\times10^{-7}\ \text{m}$

The wavelength of the light emitted is $4.86\times10^{-7}\ \text{m}$ .

6 0

3 years ago

Describe the spin of carbon-14's valence electrons and explain how you came about your answer.

Snezhnost [94]

we have to know the spin of valence electrons of carbon-14

There are four unpaired electron which are called as valence electron also.The spin of the four unpaired electron is either upfilled or down filled.

The ground state electronic configuration of C-atom is 1s²2s²2p² and one electron from 2s orbital gets excited to 2p orbital. The elctronic configuration in excited state is 1s²2s¹ $2p_{x}^{1} 2p_{y}^{1}2p_{z}^{1}$ .

The electron jumps because half-filled orbitals are more stable. Exchange energy is less than pairing energy.

8 0

3 years ago

1. A 5.05 g sample of quartz (SiO2) contains 2.36 g of silicon. What are the percentages of silicon

hammer [34]

Answer: B) 46.7% Si and 53.3% O

Explanation:

To calculate the mass percent of element in a given compound, we use the formula:

$\text{Mass percent of element}=\frac{\text{Mass of element}}{\text{total mass}}\times 100\%$

Mass of quartz $(SiO_2)$ = 5.05 g

Mass of silicon = 2.36 g

Mass of oxygen = Mass of quartz $(SiO_2)$ - mass of silicon = 5.05g - 2.36 g = 2.69 g

$\text{Mass percent of silicon}=\frac{\text{Mass of silicon}}{\text{total mass of quartz}}\times 100=\frac{2.36}{5.05}\times 100=46.7\%$

$\text{Mass percent of oxygen}=\frac{\text{Mass of oxygen}}{\text{total mass of quartz}}\times 100=\frac{2.69}{5.05}\times 100=53.3\%$

Thus the percentages of silicon and oxygen in quartz are B) 46.7% Si and 53.3% O

6 0

3 years ago