Answer:
<em>2.085 x 10^-20 J</em>
<em></em>
Explanation:
minimum energy required to produce photoelectric effect in chromium is given as hf = 7.21 x 10^-19 J
The work function of chromium Ф = 4.37 eV = 7.00151 x 10^-19 J
The minimum energy required to eject an electron from from a chromium metal E = ?
From E = hf - Ф
substituting values, we have
E = (7.21 x 10^-19) - (7.00151 x 10^-19)
E = <em>2.085 x 10^-20 J</em>
Answer:
Which statement best compares a eukaryote and a prokaryote?
A. Eukaryotes have a cell wall, while prokaryotes have a cell membrane.
*B. Eukaryotes have membrane-bound organelles, while prokaryotes have few specialized
structures.
C. Eukaryotes use active transport to move substances across the cell membrane, while
prokaryotes use facilitated diffusion.
D. Eukaryotes use flagella to move themselves through substances, while prokaryotes are not
able to move.
Explanation: its B
Answer:
<em>D. A combustion reaction</em>
Explanation:
Heat is the first one...and the secound one is kinetic
Answer:
The specific heat of the alloy 
Explanation:
Mass of an alloy
= 25 gm
Initial temperature
= 100°c = 373 K
Mass of water
= 90 gm
Initial temperature of water
= 25.32 °c = 298.32 K
Final temperature
= 27.18 °c = 300.18 K
From energy balance equation
Heat lost by alloy = Heat gain by water
[
-
] =
(
-
)
25 ×
× ( 373 - 300.18 ) = 90 × 4.2 (300.18 - 298.32)

This is the specific heat of the alloy.