8. what is the atomic number of calcium?
a. 2
b. 20
c. 40
d. 18
9. how many electrons are in a neutral atom of calcium?
a. 20
b. 30
c. 40
d. 60
10. determine the mass number of element x with 27 protons, 20 neutrons, and 30 electrons.
a. 20
b. 47
c. 57
d. 27
11. protons always equal the number of ______ in a neutral atom.
a. amu’s
b. electrons
c. neutrons
d. isotopes
12. how many neutrons does an atom with atomic number 50 and mass number 125 contain?
a. 70 neutrons
b. 75 neutrons
c. 50 neutrons
d. 120 neutrons
for questions 13 - 14, use the atom diagram below.
atom diagram with labels a, b, c, d
13. which letter in the atom diagram points to a neutron?
a. a
b. b
c. c
d. d
14. which letter in the atom diagram points to an electron?
a. a
b. b
c. c
d. d
15. an object’s resistance to change its motion is:
a. acceleration.
b. inertia.
c. friction.
d. tension.
16. what is the force exerted (push or pull) on an object by something else?
a. applied force
b. gravitational force
c. normal force
d. frictional force
17. what is a force between two surfaces that always acts in the opposite direction of the moving object?
a. applied force
b. gravitational force
c. normal force
d. frictional force
18. which of the following is the correct equation for speed?
a. ( s = t / d )
b. ( s = m imes a )
c. ( s = d / t )
d. ( s = f / d )
19. which of the following is the correct equation for force?
a. ( f = m / a )
b. ( f = m imes a )
c. ( f = d / t )
d. ( f = a / m )

Question

8. what is the atomic number of calcium?
  a. 2
  b. 20
  c. 40
  d. 18
9. how many electrons are in a neutral atom of calcium?
  a. 20
  b. 30
  c. 40
  d. 60
10. determine the mass number of element x with 27 protons, 20 neutrons, and 30 electrons.
  a. 20
  b. 47
  c. 57
  d. 27
11. protons always equal the number of ______ in a neutral atom.
  a. amu’s
  b. electrons
  c. neutrons
  d. isotopes
12. how many neutrons does an atom with atomic number 50 and mass number 125 contain?
  a. 70 neutrons
  b. 75 neutrons
  c. 50 neutrons
  d. 120 neutrons
for questions 13 - 14, use the atom diagram below.
atom diagram with labels a, b, c, d
13. which letter in the atom diagram points to a neutron?
  a. a
  b. b
  c. c
  d. d
14. which letter in the atom diagram points to an electron?
  a. a
  b. b
  c. c
  d. d
15. an object’s resistance to change its motion is:
  a. acceleration.
  b. inertia.
  c. friction.
  d. tension.
16. what is the force exerted (push or pull) on an object by something else?
  a. applied force
  b. gravitational force
  c. normal force
  d. frictional force
17. what is a force between two surfaces that always acts in the opposite direction of the moving object?
  a. applied force
  b. gravitational force
  c. normal force
  d. frictional force
18. which of the following is the correct equation for speed?
  a. ( s = t / d )
  b. ( s = m 	imes a )
  c. ( s = d / t )
  d. ( s = f / d )
19. which of the following is the correct equation for force?
  a. ( f = m / a )
  b. ( f = m 	imes a )
  c. ( f = d / t )
  d. ( f = a / m )

Accepted Answer

### Question 8
# Brief Explanations:
The atomic number of an element is equal to the number of protons in its nucleus. From the periodic table, calcium (Ca) has an atomic number of 20. The options a (2) is for helium, c (40) is the mass number of calcium, and d (18) is for argon. So the correct option is b.
# Answer:
b. 20

### Question 9
# Brief Explanations:
In a neutral atom, the number of electrons is equal to the number of protons (atomic number). Calcium has an atomic number of 20, so the number of electrons in a neutral calcium atom is 20. Option b (30) is incorrect, c (40) is the mass number, and d (60) is not related.
# Answer:
a. 20

### Question 10
# Explanation:
## Step1: Recall the formula for mass number
Mass number ($A$) is the sum of the number of protons ($p$) and neutrons ($n$), i.e., $A = p + n$.
## Step2: Substitute the given values
Given $p = 27$ and $n = 20$, so $A = 27 + 20 = 47$.
# Answer:
b. 47

### Question 11
# Brief Explanations:
In a neutral atom, the number of protons is equal to the number of electrons to balance the charge. Option a (amu's) is a unit of mass, c (neutrons) can be different (isotopes have same protons but different neutrons), and d (isotopes) are different forms of an element. So the correct option is b.
# Answer:
b. electrons

### Question 12
# Explanation:
## Step1: Recall the formula for mass number
Mass number ($A$) = number of protons (atomic number, $Z$) + number of neutrons ($n$), so $n = A - Z$.
## Step2: Substitute the given values
Given $Z = 50$ and $A = 125$, then $n = 125 - 50 = 75$.
# Answer:
b. 75 neutrons

### Question 13
# Brief Explanations:
In an atom diagram, neutrons are neutral particles in the nucleus. Typically, in such diagrams, the nucleus contains protons (positive) and neutrons (neutral). Assuming the diagram has the nucleus with A, B, D and electron C. If D is a neutron (neutral), A could be proton (positive), B maybe another proton or something else, and C is electron. So the correct option is d.
# Answer:
d. D

### Question 14
# Brief Explanations:
Electrons are negatively charged particles orbiting the nucleus. In the diagram, C is shown as an electron (orbiting), while A, B, D are in the nucleus. So the correct option is c.
# Answer:
c. C

### Question 15
# Brief Explanations:
Inertia is defined as an object's resistance to change its state of motion (either at rest or in uniform motion). Acceleration is the rate of change of velocity, friction is a force, and tension is a force in strings. So the correct option is b.
# Answer:
b. inertia

### Question 16
# Brief Explanations:
Applied force is the force exerted (push or pull) on an object by an external agent. Gravitational force is the force due to gravity, normal force is the force perpendicular to a surface, and frictional force opposes motion. So the correct option is a.
# Answer:
a. applied force

### Question 17
# Brief Explanations:
Frictional force is the force between two surfaces that opposes the motion of an object (acts in the opposite direction of motion). Applied force is the force applied, gravitational force is due to gravity, normal force is perpendicular to surface. So the correct option is d.
# Answer:
d. frictional force

### Question 18
# Brief Explanations:
Speed is defined as the distance ($d$) traveled per unit time ($t$), so the formula is $s=\frac{d}{t}$. Option a is incorrect, b is for force ($F = ma$), d is not a valid formula for speed. So the correct option is c.
# Answer:
c. $s = d/t$

### Question 19
# Brief Explanations:
From Newton's second law, the force ($F$) is equal to the mass ($m$) multiplied by acceleration ($a$), i.e., $F = m	imes a$. Option a is incorrect (should be $F = ma$), c is for speed ($s = d/t$), d is incorrect. So the correct option is b.
# Answer:
b. $F = m	imes a$

Sovi.AI - AI Math Tutor

QUESTION IMAGE

Question

Explanation:

Question 8

Step1: Recall the formula for mass number

Step2: Substitute the given values

Answer:

Question 9