What are two human activities that are harmful to birds?

Tin has many possible isotopes. Three of these isotopes are 116sn, 120sn, and 126sn. What is the mass number of each? How many p

Aneli [31]

Isotopes are defined as atoms of same element with different mass number and same atomic number.

Here, atomic number is equal to number of protons and number of electrons, it is denoted by symbol Z thus,

$Z=n_{e}=n_{p}$

and, mass number is equal to sum of number of protons and neutrons, it is denoted by symbol A thus,

$A=n_{p}+n_{n}$

The three isotopes of tin are given, Sn-116, Sn-120 and Sn-126, mass number for these three isotopes is 116, 120 and 126 respectively. Since, they are isotopes thus, atomic number remains the same that is 50.

Since, $Z=n_{e}=n_{p}$ thus, number of protons and electrons will be 50.

For Sn-116,

$A=n_{p}+n_{n}$

Or,

$116=50+n_{n}$

Or,

$n_{n}=116-50=66$

For Sn-120,

$n_{n}=120-50=70$

For Sn-126,

$n_{n}=126-50=76$

Therefore, mass number, number of protons, electrons and neutrons in all three isotopes are:

Sn-116:

Mass number= 116

Protons=50

neutrons=66

electrons=50

Sn-120:

Protons=50

neutrons=70

electrons=50

Sn-126:

Protons=50

neutrons=76

electrons=50

3 0

4 years ago

How many milliliters of a 1:2000 drug "i" solution and a 7% drug "i" solution mixed would make 120ml of a 3.5% solution of drug

yanalaym [24]

To solve this problem, let us say that:

x = volume of 1:2000 drug "i" solution

y = volume of 7% drug "i" solution

Assuming volume additive, then this forms:

x + y = 120 mL

x = 120 – y ---> 1

1:2000 also refers to 0.0005 concentrations and 7% also refers to 0.07 concentrations. By doing a component balance:

0.0005 x + 0.07 y = 0.035 (120 mL)

0.0005 x + 0.07 y = 4.2

Substituting equation 1 into this derived equation to get an equation in terms of y:

0.0005 (120 – y) + 0.07 y = 4.2

0.06 – 0.0005 y + 0.07 y = 4.2

0.0695 y = 4.14

y = 59.568 mL = 59.57 mL

From equation 1, x would be:

x = 120 - 59.57

x = 60.43 mL

Answers:

59.57 mL of 1:2000 drug "i" solution

60.43 mL of 7% drug "i" solution

3 0

3 years ago

AuB4O7 name Element i need help

coldgirl [10]

Can you ask your question more thoroughly?

7 0

3 years ago

Please help me i will mark brainliest

gulaghasi [49]

Answer:

7) Example: Gravitational force

Gravitational force, also known as gravity, is a type of non- contact force.

10) Unbalanced forces can cause an object to accelerate, make a stationary object move, or cause a moving object to stop.

12) Gravitational force, Frictional force, Magnetic force

13) Friction is beneficial when we are walking as it prevents us from slipping.

For the table, find the net force first and that would help us to find the direction and the type of force (balanced/ unbalanced).

As written in Q11, add all the forces together to determine the net force acting on an object. More specifically, add the forces that act in one direction together. Then subtract the forces acting in the other direction.

Let's look at the teddy bear (Q14 -16):

Take note that we have to look at the direction of the arrow not which side the arrow is on (left/ right of the bear).

Total force acting towards the left

= 16 +7

= 23N

Total force acting on the right= 22N

Net force

= 23 -22

= 1N towards the left

Thus, 14) Unbalanced (since the net force is not 0N)

15) 1N

15) 1N16) left

Vase question:

Total downward force

= 11 +33

= 44N

Total upward force

= 25 +19

= 44N

Net force= 0N

17) Balanced

17) Balanced18) 0N

17) Balanced18) 0N19) No direction

Bicycle question:

Total force acting towards the right

= 65 +115

= 180N

Total force to the left= 170N

Net force

= 180 -170

= 10N to the right

20) Unbalanced

20) Unbalanced21) 10N

20) Unbalanced21) 10N22) To the right

4 0

3 years ago

Carbon is considered which of the following?

Zarrin [17]

Answer: atomic element

4 0

2 years ago