The Kingdom is the highest rank in classification. It is subdivided into <span>5 major kingdoms while as </span>species is the basic unit of classification. <span><span>A </span>species can be defined as a group of interbreeding organisms that are capable of producing fertile offspring
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hope this helps u :D
0.1 M x 0.5L = 0.05 mols HCl.
Adding 25 mL 2M NaOH is
2M x 0.025 L = 0.05 mols NaOH.
What you want to do is to back off very slightly with the NaOH (you might try something like 24.95 mL which I calculate to give 0.00019 M or a pH of 3.7. Inching closer, 24.99 mL would leave H^+ of 4E-5 for pH 4.4. The problem here is two-fold.
hope it helps
First you need to work out what mass of 84g of stainless steel is nickel, and because there's 5% you can simply divide by 20, giving 4.2g
For this you can use the equation

The mass, as was worked out previously, is 4.2g
The Mr, which is found on the periodic table, is 28
Moles =

= 0.15mol
1mol = 6.023 x

atoms
So, 0.15mol = 0.15 x 6.023 x

= 9.0345 x

atoms
Your question is incomplete. However, I found a similar problem fromanother website as shown in the attached picture.
To solve this problem, you must know that at STP, the volume for any gas is 22.4 L/mol. So,
Moles O₂: 156.8 mL * 1 L/1000 mL* 1 mol/22.4 L = 0.007 moles
Mass calcium: 0.007 mol O₂ * 2 mol Ca/1 mol O₂ * 40 g/mol Ca =
<em> 0.56 g Ca</em>