As frequency decreases, wavelength…... finish this sentence

The Bantu were experts in this form of metallurgy. gold steel iron copper

son4ous [18]

they're experts in iron metallurgy

The bantu was originated from the southern part of Africa ( round republic of Congo) , and has been the expert of utilizing iron among the ancient tribe

Mostly they use it for their Agricultural system ( such as their Irrigation system, for their agricultural tools, etc)

4 0

2 years ago

Read 2 more answers

Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel ro

melamori03 [73]

Answer: The mass of nickel (II) oxide and aluminium that must be used is 18.8 g and 4.54 g respectively.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For nickel:

Given mass of nickel = 14.8 g

Molar mass of nickel = 58.7 g/mol

Putting values in equation 1, we get:

$\text{Moles of nickel}=\frac{14.8g}{58.7g/mol}=0.252mol$

For the given chemical reaction:

$3NiO(s)+2Al(s)\rightarrow 3Ni(l)+Al_2O_3(s)$

For nickel (II) oxide:

By Stoichiometry of the reaction:

3 moles of nickel are produced from 3 moles of nickel (II) oxide

So, 0.252 moles of nickel will be produced from $\frac{3}{3}\times 0.252=0.252mol$ of nickel (II) oxide

Now, calculating the mass of nickel (II) oxide by using equation 1:

Molar mass of nickel (II) oxide = 74.7 g/mol

Moles of nickel (II) oxide = 0.252 moles

Putting values in equation 1, we get:

$0.252mol=\frac{\text{Mass of nickel (II) oxide}}{74.7g/mol}\\\\\text{Mass of nickel (II) oxide}=(0.252mol\times 74.7g/mol)=18.8g$

For aluminium:

By Stoichiometry of the reaction:

3 moles of nickel are produced from 2 moles of aluminium

So, 0.252 moles of nickel will be produced from $\frac{2}{3}\times 0.252=0.168mol$ of aluminium

Now, calculating the mass of aluminium by using equation 1:

Molar mass of aluminium = 27 g/mol

Moles of aluminium = 0.168 moles

Putting values in equation 1, we get:

$0.168mol=\frac{\text{Mass of aluminium}}{27g/mol}\\\\\text{Mass of aluminium}=(0.168mol\times 27g/mol)=4.54g$

Hence, the mass of nickel (II) oxide and aluminium that must be used is 18.8 g and 4.54 g respectively.

4 0

2 years ago

What safety precautions are needed when running a brine electrolysis plant

nikdorinn [45]

Good ventilation as a product of it is pure Cl2 gas

4 0

3 years ago

What type of product is formed when acids are added to some ionic compounds?

Andru [333]

Answer:

Your Answer is Option A that is Gas.

3 0

1 year ago

Maggie has 4 binders with 30 stamps in each binder. She has 3 binders with 36 baseball cards in each binder. If she gives away 4

Sliva [168]

Answer:

The number of stamps and cards Maggie has left if she gives 45 stamps to a friend is 183

Explanation:

If Maggie gives 45 stamps to a friend, you must calculate the number of stamps and cards she has left.

You know Maggie has 4 folders with 30 stamps in each folder. So the number of stamps she owns is calculated as:

4 folders*30 stamps in each folder= 120 stamps

If Maggie gives 45 stamps to a friend, then the number of stamps she has left will be calculated as the difference (the subtraction) between the stamps she owned and the ones she gives away:

120 stamps - 45 stamps= 75 stamps

On the other hand, she has 3 binders with 36 baseball cards in each binder. So the number of cards she owns is calculated as:

3 binders * 36 baseball cards in each binders= 108 baseball cards

The number of stamps and cards you have left is calculated as:

75 stamps + 108 baseball cards= 183

The number of stamps and cards Maggie has left if she gives 45 stamps to a friend is 183

4 0

2 years ago