Part 1 out of 2 do both members of the following pairs have the same number of protons? neutrons? electrons? 41 k 19 and 42 ca 20 protons are equal. protons are not equal. neutrons are equal. neutrons are not equal. electrons are equal. electrons are not equal. 28 si 14 and 29 si 14 protons are equal. protons are not equal. neutrons are equal. neutrons are not equal. electrons are equal. electrons are not equal. 58 mn 25 and 58 fe 26 protons are equal. protons are not equal. neutrons are equal. neutrons are not equal. electrons are equal. electrons are not equal.

These are three questions and three complete answers.

Question 1. A) Pair: ⁴¹ ₁₉ K and ⁴² ₂₀ Ca

Explanation:

The given notation is used to identify specific isotopes or atoms.

The letter is the chemical symbol. K is potassium, and Ca is calcium.

The superscript to the left of the symbol is the mass number, and the subscript to the left of the symbol is the atomic number.

Hence:

Atomic number is the number of protons in the nucleus of the atom. Hence:

Also, for neutral atoms (which the given pairs are) the number of electrons is equal to the number of protons. Hence:

Mass number is the sum of the number of protons and the number of neutrons. Hence:

Conclusion:

Queston 2. B) Pair ²⁸ ₁₄ Si and ²⁹₁₄ Si

Explanation:

Pair ²⁸ ₁₄ Si and ²⁹₁₄ Si are different atoms of the same element (Si). So, they have the same atomic number (14 protons) but different mass number (28 and 29), due to different number of neutrons in their nuclei.

Remember, the subscript to the left of the symbol tells the atomic number, which is a constant for every atom of the same element. This pair is of Si, so both atoms have the same number of protons, which  is 14 (the atomic number).

Again, since they are neutral atoms (atoms with zero net charge), the number of electrons and  the number protons are equal. So, both atoms have the same number of electrons.

As per the number of neutrons, since the mass number is the sum of the protons and neutrons, given that the mass number of one atom is 28 and the mass number of the other is 29 (being the number of protons equal) you conclude that they have different number of neutrons.

Conclusion:

Question 3. C) Pair ⁵⁸ ₂₅ Mn and ⁵⁸ ₂₆ Fe

Explanation:

        i) Left subscript, 25, means atomic number or number of protons = 25.

        ii) Left superscript means mass number = protons + neutrons = 58

        iii) ∴ neutrons = 58 - 25 = 33

         iv) neutral atoms ⇒ number of electrons = number of protons = 25

        i) Left subscript, 26, means atomic number or number of protons = 26.

        ii) Left superscript means mass number = protons + neutrons = 58

        iii) ∴ neutrons = 58 - 26 = 32

        iv) neutral atoms ⇒ number of electrons = number of protons = 26

Hence, for this pair the conclusion is:

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )