Answer:
c
Explanation:
neutrons have no charge
protons and electrons have opposite charges and balance each other out in equal numbers
The wall would absorb extra heat during the day when the sun is out, then release the heat back into the room when the sun goes down.
Question 3
Explanation:
answer -A /A chemical reaction happens when substances break apart or combine to form one or more new substances. New substances form when bonds break and new bonds form. The chemical properties of the new substances are different from those of the original substances. ... Some chemical reactions produce a precipitate.
answer- B /Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products
Answer:
The final temperature of water is 54.5 °C.
Explanation:
Given data:
Energy transferred = 65 Kj
Mass of water = 450 g
Initial temperature = T1 = 20 °C
Final temperature= T2 = ?
Solution:
First of all we will convert the heat in Kj to joule.
1 Kj = 1000 j
65× 1000 = 65000 j
specific heat of water is 4.186 J /g. °C
Formula:
q = m × c × ΔT
ΔT = T2 - T1
Now we will put the values in Formula.
65000 j = 450 g × 4.186 J /g. °C × (T2 - 20°C )
65000 j = 1883.7 j /°C × (T2 - 20°C )
65000 j/ 1883.7 j /°C = T2 - 20°C
34.51 °C = T2 - 20°C
34.51 °C + 20 °C = T2
T2 = 54.5 °C
Molecular Weight (MW) is the sum of the atomic weights/masses (AM) of every atom in a compound or molecule. Thus, we would add the AM of Mg + 2×[N+(O×3)]:
Mg = 24.31
N = 14.01
O = 16
So we have: Mg + 2×[N+(O×3)] = 24.31 + 2×[14.01+(16×3)] = 24.31+2×[14.01+48] = 24.31+ 2×62.01 = 24.31+124.02 = 148.33
C) is the correct answer
