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
xeze [42]
3 years ago
9

HELP!! IT'S WORK 25+ POINTS AND ONLY HAVE 20 MINUTES LEFT!! Which of these are characteristics of reptiles? Check all that apply

.
They undergo internal fertilization.
Their urine is concentrated.
They use their skin for gas exchange.
They have two-chambered hearts.
They are covered in scales.
Chemistry
1 answer:
monitta3 years ago
7 0
They undergo internal fertilization.
They are covered in scales.

(Their scales are too thick to be permeated by oxygen, their hearts are three-chambered, and their <span>kidneys are unable to produce liquid urine more concentrated than their body fluid.)</span>
You might be interested in
Which is a pure substance?<br><br> A) Mixture <br><br> B)Solution <br><br> C)Element
Vinil7 [7]

Answer:

The answer is C Element

7 0
3 years ago
If 6.00 g of CaCl2 • 2 H2O and 5.50 g of Na2CO3 are allowed to react in aqueous solution, what mass of CaCO3 will be produced? P
Andre45 [30]

Answer:

6.00 g CaCl₂ .2H₂O /1 × 1 mol CaCl₂ .2H₂O / 147 g CaCl₂ .2H₂O × 0.04 mol CaCO₃/ 0.04 mol of  CaCl₂ .2H₂O  × 100 g CaCO₃ /  1 mole CaCO₃ = 4 g

5.50 g Na₂CO₃   /1 × 1 Na₂CO₃  / 106 g Na₂CO₃ × 0.05 mol CaCO₃/ 0.05 mol of Na₂CO₃  × 100 g CaCO₃ /  1 mole CaCO₃ = 5 g

Explanation:

Given data:

Mass of CaCl₂.2H₂O = 6.00 g

Mass of Na₂CO₃ = 5.50 g

Mass of CaCO₃ produced = ?

Solution:

Number of moles of CaCl₂.2H₂O.

Number of moles = mass/ molar mass

Number of moles = 6.00 g/ 147 g/ mol

Number of moles = 0.04 mol

Number of moles of Na₂CO₃:

Number of moles = mass/ molar mass

Number of moles = 5.50 g/ 106 g/ mol

Number of moles = 0.05 mol

Chemical equation:

CaCl₂  +  Na₂CO₃   →   CaCO₃ + 2NaCl

Now we will compare the moles of CaCO₃  with Na₂CO₃  and CaCl₂ through balanced chemical equation .

                      CaCl₂              :               CaCO₃

                             1                :                1

                       0.04               :            0.04

Mass of CaCO₃:

Mass = number of moles × molar mass

Mass = 0.04 mol× 100 g/mol

Mass = 4 g

6.00 g CaCl₂ .2H₂O /1 × 1 mol CaCl₂ .2H₂O / 147 g CaCl₂ .2H₂O × 0.04 mol CaCO₃/ 0.04 mol of  CaCl₂ .2H₂O  × 100 g CaCO₃ /  1 mole CaCO₃ = 4 g

                     Na₂CO₃            :            CaCO₃

                          1                   :                1

                       0.05               :            0.05

Mass of CaCO₃:

Mass = number of moles × molar mass

Mass = 0.05 mol× 100 g/mol

Mass = 5 g

5.50 g Na₂CO₃   /1 × 1 Na₂CO₃  / 106 g Na₂CO₃ × 0.05 mol CaCO₃/ 0.05 mol of Na₂CO₃  × 100 g CaCO₃ /  1 mole CaCO₃ = 5 g

                     

5 0
3 years ago
During which of the following stages of thunderstorm development is the downdraft significantly stronger than the updraft?
Rus_ich [418]
The downdraft is significantly stronger than the updraft in either the dissipating stage (B) or the mature stage (C). 

Hope this helped :)
5 0
4 years ago
Read 2 more answers
HELP!!!! ILL GIVE THE CROWN THINGY THING!!!!!!!!!! DUE SOON!!!!!!!!! PLS HELP!!!!!!!!!!
xxTIMURxx [149]

Answer: A. Most radiation reaching Earth from space is blocked by the atmosphere. Therefore, some telescopes must be placed above the atmosphere.

Explanation: Astronomers have a huge problem detecting radiation from space because the Earth's atmosphere blocks most of it and stops it from reaching the surface.

Hope this helps :)

8 0
3 years ago
Can someone please help me in this question?
Monica [59]

Answer: the beaker with a higher boiling point is B.

Explanation:

since it contains more mass/ volume it takes up more time to heat up.

hope this helps!

5 0
4 years ago
Other questions:
  • Barium selenide formula
    8·1 answer
  • Which of the following sources of radiation produced from nuclear power plants poses the largest threat to humans?
    15·2 answers
  • Given the reaction: 6 NaOH + 2 Al ---&gt; 2 Na3AlO3 + 3 H2
    12·1 answer
  • What are the disadvantages of synhetic rubber?
    7·1 answer
  • If all people understood the common heritage that we have with the Earth and our environment - namely, that the very atoms that
    12·1 answer
  • Does a dry cell have local action?​
    7·1 answer
  • A gas occupies a volume of 500. Milliliters at a pressure of 38.0 kPa and a temperature of 298 K. At what temperature will the g
    6·1 answer
  • 28. If the total pressure of a mixture of four gases (neon, carbon dioxide, oxygen and hydrogen) is 1245 mm
    6·1 answer
  • What are the cations found in the body
    9·1 answer
  • Identify the limiting reactant when 9.65-g H2SO4 reacts with 6.10-g of NaOH.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!