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
kotykmax [81]
3 years ago
6

Kostya randomly chooses a number from 1 to 10. What is the probability he chooses a number less than 5?

Chemistry
2 answers:
Furkat [3]3 years ago
8 0
It’s A. 1/2 -Correct answer.
Ghella [55]3 years ago
3 0
A. 1/2

Explanation- There is a 5/10 chance of choosing on of the numbers which simplifies to 1/2
You might be interested in
26 g of zinc combines with 12.8 g of sulfur. What is the empirical formula of zinc sulfide?
Alisiya [41]
Moles of Zn: 26 / 65 = 0.4
Moles of S: 12.8 / 32 = 0.4

Molar ratio of Zn : S = 1 : 1
Empircal formula: ZnS

The answer is C
7 0
4 years ago
If 3.1 moles of potassium chloride react with oxygen, how many moles of potassium chlorate would be produced?
Likurg_2 [28]

Answer: 19 dollar fortnite card Explanation:who wants it

7 0
3 years ago
Determine the possible traits of the calves if:
White raven [17]

Answer:

1. All red calves i.e. RR

2. All roan calves i.e RW

3. 2 red calves (RR) and two roan calves (RW)

Explanation:

According to this question, a gene coding for fur colour in cattle is involved. Red alleles (R) and white alleles (W) are co-dominant to produce a roan cattle (RW). The possible traits of the following crosses are (see attached punnet square):

1) A red bull (RR) is mated to a red (RR) cow: All red calves i.e. RR

2) A red (RR) bullis mated with white (WW) cow: All roan calves i.e RW

3) A roan bull (RW) is mated with red (RR) cow: 2 red calves (RR) and two roan calves (RW).

7 0
3 years ago
A 111.6 gram sample of iron (MW=55.8) was heated from 0 degrees C to 20 degrees C. It absorbed 1004 Joules of energy. What is th
qwelly [4]
Use the equation q=ncΔT.
q= heat absorbed our released (in this case 1004J)
n= number of moles of sample ( in this case 2.08 mol)
c=molar heat capacity 
ΔT=change in temperature (in this case 20°C)
You have to rewrite the equation for c.
c=q/nΔT
c=1004J/(2.08mol x 20°C)
c=24.1 J/mol°C
 
I hope this helps
7 0
3 years ago
A rock contains 0.623 mg of 206Pb for every 1.000 mg of 238U present. Assuming that no lead was originally present, that all the
maxonik [38]

Answer:

t = 3,496x10⁹ years

Explanation:

The decay of ²³⁸U is:

²³⁸U → ²⁰⁶Pb + 8He + 6e⁻

Moles of ²⁰⁶Pb presents in 0,623mg are:

0,623x10⁻³g×(1mol / 206g) = 3,02x10⁻⁶ moles of ²⁰⁶Pb.

These moles are equals to moles of ²³⁸U before decay, that means, 3,02x10⁻⁶ moles²³⁸U

In grams:

3,02x10⁻⁶ moles²³⁸U× (238g / 1mol) = 7,20x10⁻⁴ g ²³⁸U = 0,720 mg²³⁸U

That means initial ²³⁸U was 1,000mg + 0,720mg =<em> 1,720mg</em>

Applying the formula:

ln (N₀/N) t₁₂ = t ln2

Where N₀ is initial amount of uranium (1,720mg), N is concentration of uranium (1,000mg),  half-life time is a constant (t₁₂= 4,468x10⁹ years) and t is the time transcurred for the reaction. Replacing:

ln(1,720/1)*4,468x10⁹ years = t ln2

<em>t = 3,496x10⁹ years</em>

<em></em>

I hope it helps!

6 0
3 years ago
Other questions:
  • An adult rhino xan have a mass of 1400 kg the mass of a small egret is about 0.76kg. what is the radio of these two masses? how
    11·1 answer
  • Calculate the mass of 3.05 buckets of golf balls.
    6·1 answer
  • The percentage yield for the reaction
    15·1 answer
  • Through electrolysis, a student collects 6.6 g of hydrogen gas and 52.4 g of oxygen gas. The reaction was allowed to proceed to
    7·1 answer
  • Is Fe a element or a compound?
    5·2 answers
  • The environment can be changed in many ways, both by humans and nature. Some of these changes are good, while some are not. Sort
    9·1 answer
  • Identify each definition that applies to the compound in red. Check all that apply.
    14·2 answers
  • true or false You have to have the same number of each type of atom on the left-and right-handside of a chemical equation
    8·1 answer
  • What are the three components of soil texture? <br><br> Hurry please help!
    6·1 answer
  • 6. Which of the following statements is one of the postulates in Dalton's atomic theory?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!