Question

for $_{38}^{85}sr$, there are
47 protons and 38 neutrons.
85 protons and 47 neutrons.
85 protons and 38 neutrons.
38 protons and 85 neutrons.
38 protons and 47 neutrons.
question 3 (1 point)
when a positron is emitted from the nucleus of an atom, the
decreases by one unit.
increases by two units.
increases by one unit.
remains the same.
decreases by two units.
question 4 (1 point) saved
the product from the alpha decay of $_{92}^{235}u$ is
$_{80}^{233}ra$.
$_{90}^{231}th$.
$_{93}^{235}np$.
$_{11}^{239}p$

Explanation:

Step1: Identify the components of an atom

In the notation \(_{38}^{85}\text{Sr}\), the subscript \(38\) is the atomic number (\(Z\), number of protons), and the superscript \(85\) is the mass number (\(A\), sum of protons and neutrons).

Step2: Calculate the number of neutrons

Use the formula \(N = A - Z\). Here, \(A = 85\) and \(Z = 38\), so \(N=85 - 38=47\).

Answer:

38 protons and 47 neutrons.