Metallic properties head to the left.
Answer:
A. Neither the subjects nor the researchers can bias the results.
Explanation:
As described, a double- blind study is one in which the researcher and his study does not know the person receiving the actual treatment.
Researchers can be bias in their studies as they seek to establish and fine tune results in the way the best favors them. A double-blind study helps to bridge this gap to prevent bias that might be introduced into an experimental set up or while interpreting results.
Answer:
6g O2
Explanation:
Mole to mole ratio:
A balanced chemical equation shows a chemical reaction while maintaining the law of conservation of mass. The coefficients of the substances are known to be very helpful in computations as they represent the equivalent amounts of moles of the species that would be participating in the reaction.
We set up the chemical equation and then find the balanced chemical expression.
S+O2→SO3
Balance
2S+3O2→2SO3
We use the following values for the variables:
mS=4.0 gm
We proceed with the solution.
mO2= 4 g S × 1 mol S/ 32 g S × 3 mol O2/ 2 mol S × 32g O/ 1 mol O2
mO2 = 6 g
learn
brainly.com/question/17961582?referrer=searchResults
The heat of the reaction is an extensive property: it is proportional to the quantity of the quantity that reacts.
The change in enthalpy is a measured of the heat evolved of absorbed.
When the heat is released, the change in enthalpy is negative.
The reaction of 2 moles of Na develops 368.4 kj of energy.
Calculate the number of moles of Na in 1.90 g to find the heat released when this quantity reacts.
Atomic mass of Na: 23 g/mol
#mol Na = 1.90 g / 23 g/mol = 0.0826 mol
Do the ratios: [368.4 kj/2mol ] * 0.0826 mol = 15.21 kj.
Then the answer is that 15.21 kj of heat is released (evolved)
