Answer:
4.5 kg/L
Explanation:
Density is 4.5g/mL and it means that in 1 mL of volume, the mass contained is 4.5 g.
Let's make a rule of three
1L = 1000 mL
1 mL has a mass of 4.5 g
1000 mL would have 4500 g
Our new density would be 4500 g/L, but we may convert the g to kg
1 kg / 1000 g . 4500 g = 4.5 kg
In conclusion 4.5 g/mL = 4.5 kg/L
Answer:
81°C.
Explanation:
To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat released from water (Q = - 1200 J).
m is the mass of the water (m = 20.0 g).
c is the specific heat capacity of water (c of water = 4.186 J/g.°C).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = final T - 95.0°C).
∵ Q = m.c.ΔT
∴ (- 1200 J) = (20.0 g)(4.186 J/g.°C)(final T - 95.0°C ).
(- 1200 J) = 83.72 final T - 7953.
∴ final T = (- 1200 J + 7953)/83.72 = 80.67°C ≅ 81.0°C.
<em>So, the right choice is: 81°C.</em>
The value of X is 10 hence the formula of unknown hydrate sodium sulfate is NaSO4.10 H20
calculation
step 1:find the moles of NaSO4 and the moles of H2O
moles= mass/molar mass
moles of Na2SO4=1.42÷142=0.01 moles
moles of H20= mass of H2O/molar mass of H2O
mass of H2O= 3.22-1.42=1.8g
mole of H2O is therefore 1.8÷18=0.1 moles
step 2: find the mole ratio by dividing each mole by smallest number of mole (0.01)
that is Na2So4= 0.01/0.01 =1
H2O= 0.1/0.01=10
<span>The element gold has 32 isotopes, ranging from A =173 to A = 204. during alpha decay Au will loose 2 in atomic number and 4 in mass number . it will form a iridium isotope and helium . according to the above statement, the balanced equation for the alpha decay of gold 173 will be given as below.
173 169 4
79 Au-------------->77 Ir + 2He</span>
Answer:
Dust and smoke.
Explanation:
Dust and smoke are two different particles present in the air. Dust and smoke are different from one another due to their origin. Smoke formed from burning of materials while dust refers to the soil particles lifted by the wind due to their light weight. Dust and smoke are similar to each other due to their small in size, infinite number means uncountable and light weight.
