When water freezes into ice, some of the properties have change. What stays the same.

Answer: 1: Ice Melting is a physical change. When liquid water (H2O) freezes into a solid state (ice), it appears changed; However, this change is only physical as the the composition of the constituent molecules is the same: 11.19% hydrogen and 88.81% oxygen by mass.

Have a goood day!

5 0

2 years ago

Write a balanced equation for the following:

Ket [755]

(ANS1)— P4 + 5O2 ---> 2P2O5

(ANS2)— C3H8 + 5O2---> 3CO2 + 4H20

(ANS3)— Ca2Si + 4Cl2 ---> 2CaCl2 + SiCl4

7 0

2 years ago

9) Which element in each pair has the larger ionization energy?

erastovalidia [21]

I think the answer is C.

6 0

2 years ago

5 drops of 0.15 M Ki added to<br>40 drops of Na2S2O3<br>What is the final concentration of ki?

rjkz [21]

Answer:

$\boxed{\text{0.017 mol/L}}$

Explanation:

Na₂S₂O₃ solution does not react with KI (it reacts with I₂), so it is simply diluting the KI, and we can use the dilution formula.

$c_{1}V_{1} = c_{2}V_{2}$

Data:

c₁ = 0.15 mol·L⁻¹; V₁ = 5 drops

V(Na₂S₂O₃) = 40 drops

Calculations:

(a) Calculate the total volume

V₂ = 5 + 40 = 45 drops

(b) Calculate the concentration

0.15 × 5 = c₂ × 45

0.75 = 45c₂

$c_{2} = \dfrac{0.75 }{45} = \boxed{\textbf{0.017 mol/L}}$

3 0

2 years ago