Answer:
A & D
Explanation:
A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.
From the options, only options A & D fits this definition of single-displacement reactions.
For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.
For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.
The other options are not correct because they don't involve only and element and a compound on each side of the reaction.
Answer:
Solid materials that do not possess an orderly arrangement of atoms are called glasses (mineraloids).
Explanation:
A Mineraloid is a natural, inorganic, amorphous (lacking "defined chemical composition") solid body that does not exhibit crystallinity. It exhibits characteristics similar to those of minerals, but does not have the "ordered atomic structure" necessary to meet the definition of a mineral.
Glasses or colloids have a totally random structure on an atomic scale. They are amorphous and get the honorary name of mineraloid.
<u><em>Solid materials that do not possess an orderly arrangement of atoms are called glasses (mineraloids).</em></u>
Answer:
Explanation:
Given that,
Mass of star M(star) = 1.99×10^30kg
Gravitational constant G
G = 6.67×10^−11 N⋅m²/kg²
Diameter d = 25km
d = 25,000m
R = d/2 = 25,000/2
R = 12,500m
Weight w = 690N
Then, the person mass which is constant can be determined using
W =mg
m = W/g
m = 690/9.81
m = 70.34kg
The acceleration due to gravity on the surface of the neutron star is can be determined using
g(star) = GM(star)/R²
g(star) = 6.67×10^-11 × 1.99×10^30 / 12500²
g (star) = 8.49 × 10¹¹ m/s²
Then, the person weight on neutron star is
W = mg
Mass is constant, m = 70.34kg
W = 70.34 × 8.49 × 10¹¹
W = 5.98 × 10¹³ N
The weight of the person on neutron star is 5.98 × 10¹³ N
The sad ball does not rebound after it strikes the block. This means that the collision is inelastic. If two sad balls collide with each other, we can assume completely inelastic collision. Since momentum is conserved, the kinetic energy during the collision would be twice that of each of the ball's, half of the kinetic energy of each ball will be dissipated.