“…We used the reciprocals of the squares of the uncertainties reported in tables 5 to 7 as weighting factors in the regressions, and values of the resulting c i are given in table 8. The regression surfaces for equation (3), our experimental C p,/ values from tables 5 to 7, and the literature C p,/ values [4,[12][13][14]20,21] for the three aqueous urea compounds are shown in figures 4 to 6. The differences between our regression surfaces and values of C p,/ from the literature are as follows: for urea, average difference D = +0.3 J AE K À1 AE mol À1 , range of differences D = À12.7 J AE K À1 AE mol À1 [13] to D = +5.9 J AE K À1 AE mol À1 [13]; for 1,1-dimethylurea, average difference D = +1.6 J AE K À1 AE mol À1 , range of differences D = +6.0 J AE K À1 AE mol À1 [4] to D = À3.3 J AE K À1 AE mol À1 [4]; and for N,N 0 -dimethylurea, average difference D = +6.3 J AE K À1 AE mol À1 , range of differences D = +11.3 J AE K À1 AE mol À1 [4] to D = +1.9 J AE K À1 AE mol À1 [4].…”