22, because you just add the protons and neutrons (12 + 10)
Answer : Yes , H2SO4 is an arrhenius acid
<h2>Explanations : </h2>
• An ,Arrhenius acid ,is a substance that ,dissociates, in water to form ,hydrogen ions (H+).
,
• In other words, an arrhenius acid increases the H+ ion concentration in aqueous solution.
,
• This can be represented by the equation :

• Therefore, H2SO4 is a strong arrhenius acid.
Answer:
Density, melting point. and magnetic properties
Explanation:
I can think of three ways.
1. Density
The density of Cu₂S is 5.6 g/cm³; that of CuS is 4.76 g/cm³.
It should be possible to distinguish these even with high school equipment.
2. Melting point
Cu₂S melts at 1130 °C (yellowish-red); CuS decomposes at 500 °C (faint red).
A Bunsen burner can easily reach these temperatures.
3. Magnetic properties
You can use a Gouy balance to measure the magnetic susceptibilities.
In Cu₂S the Cu⁺ ion has a d¹⁰ electron configuration, so all the electrons are paired and the solid is diamagnetic.
In CuS the Cu²⁺ ion has a d⁹ electron configuration, so all there is an unpaired electron and the solid is paramagnetic.
A sample of Cu₂S will be repelled by the magnetic field and show a decrease in weight.
A sample of CuS will be attracted by the magnetic field and show an increase in weight.
In the picture below, you can see the sample partially suspended between the poles of an electromagnet.
Answer:
6.707 × 10¹⁷
Explanation:
From the information given:
40 ^ K kütlesi = sütteki K kütlesi × 40 ^ K / 100 kütle yüzdesi
nerede;
sütteki K kütlesi = 1.65 mg of K/mL × 225 mL = 371.25 mg of K
∴
40 ^ K kütlesi = 371.25 × 0.012/100
40 ^ K kütlesi = 0,04455 mg = 4.455 × 10⁻⁵ grams
40 ^ K mol sayısı = 40 ^ K kütlesi / molar kütle
= 4.455 × 10⁻⁵/40
= 1.11375 × 10⁻⁶
Son olarak, 40 ^ K = mol × Avogadro sayısı atomları
= 1.11375 × 10⁻⁶ × 6.022 × 10^23
= 6.707 × 10¹⁷
In order to do this, we have to first know the significant figure rules.
<span>Rule #1: All non-zero digits are significant. (1234)
Rule #2: Zeros in front of a number are not significant. (0.093)
Rule #3: Zeros between non-zero digits are significant. (78309)
Rule #4: Zeros at the end of a number are significant if there is a decimal point in the number. (0.05470)
So by going by the rules, 56.0g has three sig figs, because there is a decimal point.
0.0004m only has one sig fig, according to Rule #2.
1003ml has 4 sig figs, because the zeroes are wedged in the two sig fig numbers.
And lastly, 0.0350s has 3 sig figs because the number after a decimal point counts.
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