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2 years ago

I need to know how to find atoms on a periodic table.

Chemistry

1 answer:

Juli2301 [7.4K]2 years ago

7 0

Answer:

you get atoms number left down the element example hydrogen has 1 atoms number and mass number.

You might be interested in

What is the general form of a chemical reaction

Eddi Din [679]

So there are basically five types of chemical reactions which have their general formulas.

They are:
1. Combination reaction
General formula : A+B = AB

2. Decomposition reaction
General formula: AB = A+B

3. Single displacement reaction
General formula: AB+C = CB + A

4. Double displacement reaction
General formula: AB+CD = CB+AD

5. Acid-base reaction
General formula: A+B = S+W

You should check and compare with examples.

4 0

2 years ago

Suppose 180 ml of 3.52x10^-4 M NaOH is mixed with 220 mL of 2.47x10^-4 M MgCl2.

velikii [3]

When in water, MgCl2 dissociates into magnesium ions and Cl- ions and NaOH into Na and OH ions. The equation is as follows:

MgCl2 = Mg2+ + 2Cl-
NaOH = Na+ + OH-

The initial concentrations are as follows:

[Mg2+] = .220( 2.47x10^-4) / .220+.180 = 1.36x10^-4 M Mg2+
[OH-] = .180 (3.52x10^-4) / .220+.180 = 1.58x10^-4 M OH-

6 0

3 years ago

Which of the following could be the subsh

andreev551 [17]

Answer:

$2s^2 2p^2$

Explanation:

Group 4A contains a total of 4 electrons for each atom in their valence shell. Filling the orbital diagram, let's say, for carbon, notice that when we start with period 2, we have two elements in the s-block, that is, lithium and beryllium. They correspond to the two s electrons that belong to the valence shell of carbon.

Moving on, we have boron and carbon, the remaining 2 electrons. Now, starting with boron, we're in the p-block.

That said, looking at the second period, the electron configuration for the valence shell of a group 4A element would be:

$2s^2 2p^2$

6 0

3 years ago

If 25.5g of sodium thiosulphate was dissolved in 40g of distilled water at 25°C,

zhenek [66]

Answer:

Formula: Na2S2O3

we get solubility.

Divide the mass of the compound by the mass of the solvent and then multiply by 100 g to calculate the solubility in g/100g .

Solution given:

mass of sodium thiosulphate [m1]=25.5g

mass of water [m2]=40g

at temperature [t]=25°C

we have

solubility in g/dm^3 : $\frac{solute in gram}{solvent in gram} *100$

= $\frac{25.5}{40}*100$
=63.75g /litre=63.75g/dm³

solubility in g/dm^3 :63.75g/dm³

now

solubility of the solute in mol/dm^3=:63.75g/dm³/178=0.4 mol/dm³

6 0

2 years ago

How many pi bonds are in the oxalate ion (C2O42-)?

suter [353]

Answer:there are 13

Explanation:

4 0

2 years ago