Lions walk on 4 legs, humans walk on 2. female lions live in groups but are taken over by groups of male lions from time to time, human adults tend to live alone or in pairs with their offspring. Humans can talk and lions cannot. lions have manes around the face.
Earth's magnetic field doesn't have much to do with tectonic plates. But both are caused by movement of the magma. The magnetic field is caused by electrical currents flowing in the magma, roughly parallel with the Equator. Tectonic plates move around the surface of the Earth over the liquid magma.
So I'd go with B. mantle convection currents
Answer:
Creo que es D pero no tan segura
Explanation:
Answer:
65.4%
Explanation:
The redox reaction is a 1:1:1 reaction because the reagents suffer a double displacement reaction, and the substance that is substituted have the same charge (H+ and Br-), thus, we first need to know which of the reagents is the limiting.
Let's test the 4-nitrobenzaldehyde as the limiting. The mass needed for sodium borohydride (m) is the mass given of 4-nitrobenzaldehyde multiplied by the stoichiometric mass of sodium borohydride divided by the stoichiometric mass of 4-nitrobenzaldehyde. The stoichiometric mass is the number of moles in the stoichiometric representation (1:1:1) multiplied by the molar mass, so:
m = (4.13 * 37.83*1)/(151.12*1)
m = 1.034 g
So, the mass needed of the other reagent is larger than the mass that was given, so, it will be the limiting, and the stoichiometric calculus must be done with it.
The mass of the product that was expected is then:
m = (0.700*153.14*1)/(37.83*1)
m = 2.83 g
The percent yield is the mass that was formed divided by the expected mass, and then multiplied by 100%:
%yield = (1.85/2.83)*100%
%yield = 65.4%
Br + Br -> Br2 (covalent bond)
<span>forming of bonds releases energy, since the Br's are at a lower energy state as Br2
Answer is #3</span>
