1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vesna_86 [32]
3 years ago
15

Pls help me tell me how to do this question. i only need the answer for the first 2.pls

Chemistry
1 answer:
Delvig [45]3 years ago
7 0

Answer:

Explanation:

55 and 918

You might be interested in
Which is a chacteristic of a solution?
Setler [38]

Answer:

A solution is a homogeneous mixture of two or more substances. The particles of solute in a solution cannot be seen by the naked eye. A solution does not allow beams of light to scatter.

Explanation:

8 0
4 years ago
How do scientists test ideas about chemical evolution?
maksim [4K]
I think they test ideas about chemical evolution by doing experiments. Hope this helps
4 0
3 years ago
Read 2 more answers
What do we call genes
qwelly [4]

Hi there so i need one more brainliest mark so if i get it right can i get brainliest please  :)

A gene is the basic physical and functional unit of heredity. Genes are made up of DNA. Some genes act as instructions to make molecules called proteins. However, many genes do not code for proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases

4 0
3 years ago
Thorium-234 has a half-life of 24.1 days. How many grams of a 150 g sample would you have after 120.5 days?
chubhunter [2.5K]

Answer:

8.625 grams of a 150 g sample of Thorium-234  would be left after 120.5 days

Explanation:

The nuclear half life represents the time taken for the initial amount of sample  to reduce into half of its mass.

We have given that the half life of thorium-234 is 24.1 days. Then it takes 24.1 days for a Thorium-234 sample to reduced to half of its initial amount.

Initial amount of Thorium-234 available as per the question is 150 grams

So now  we start with 150 grams  of Thorium-234

150 \times \frac{1}{2}=24.1

75 \times \frac{1}{2} =48.2

34.5 \times \frac{1}{2} =72.3

17.25 \times \frac{1}{2} =96.4

8.625\times \frac{1}{2} =120.5

So after 120.5 days the amount of sample that remains is 8.625g

In simpler way , we can use the below formula to find the sample left

A=A_{0} \cdot \frac{1}{2^{n}}

Where

A_0  is the initial sample amount  

n = the number of half-lives that pass in a given period of time.

7 0
3 years ago
Two forces are acting on a wheelbarrow.One force is pushing to the right and an equal force is pushing to the left.What can you
andreev551 [17]
B. It is not accelerating since equal and opposite forces cancel each other. Hope it helps
7 0
4 years ago
Read 2 more answers
Other questions:
  • The process of water migrating from areas of low electrolyte concentration to area of high electrolyte concentration is called —
    5·1 answer
  • According to the molecular orbital (mo) treatment of the no molecule, what are the bond order and the number of unpaired electro
    10·1 answer
  • How many total atoms are in 0.450 grams of P2O5
    13·1 answer
  • What happens during a hurricane ??
    7·1 answer
  • 1. Using a triple beam balance and a graduated cylinder, a student collected data on a sample of an
    11·1 answer
  • Energy from the Sun arrives at the top of the Earth's atmosphere with an intensity of 1.1 kW/m2 . How long does it take for 1.91
    11·1 answer
  • The parts of the scientific method have to be followed in one specific order in all investigations. True False
    10·1 answer
  • Humans exhale carbon dioxide when they breathe. If the concentration of carbon dioxide in the air that
    10·1 answer
  • The potential difference across the terminals of a battery of e.m.f. 12 V and internal resistance 2 ohm drops to 10 V when it is
    6·1 answer
  • What can you coil and make a solenoid have an even stronger field? *
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!